PDU set QOS based multi access handling for data traffic such as XR traffic

Abstract

Examples are presented for PDU Set QoS based MA handling for data traffic. Rules are enabled to use PSLR, PSD thresholds to split and steer PDUs for PDU Sets for MA data traffic across multiple accesses for n3GPP and 3GPP accesses. These rules allow a UE and UPF to (re)distribute UL and DL flows (e.g., UL and DL data traffic) over these accesses. Alternatively, rules are used to indicate that, if PDU set handling is not supported by both accesses, then normal PDU handling and rules are to be used. If PDU set handling is supported by both accesses, then PDU Set handling and rules are to be used. The UE and UPF use such handling and rules to (re)distribute UL and DL flows over these accesses.

Description

PDU Set QoS Based Multi Access Handling for Data Traffic such as XR TrafficTECHNICAL FIELD

[0001] Examples of embodiments herein relate generally to cellular networking and, more specifically, relate to multi-access (MA) handling where data transfer occurs using accesses for non-3GPP (third generation partnership project) and 3GPP access nodes.BACKGROUND

[0002] XR (extended reality) and media services for XR (XRM) require high data rate and low latency. For XR services, there are multiple types of traffic, e.g., audio, video, sensor, pressure, and tactile, all generated to enhance a user’s experience. In the existing 5GS (fifth generation, 5G, system), the policy control is applied to a single data flow. In a traditional mobile network since GPRS (general packet radio service), the QoS (quality of service) control is based on the concept of flow and packet (e.g., a protocol data unit, PDU). However, such scheduling did not consider the relationship between packets, which are important for especially interactive media services like XR, since it is common that one unit of a media layer needs to be delivered via multiple packets. Furthermore, different media units may contribute differently to the user experience, even when they are within a single steam. Thus, the importance of these media units is not unique from a media layer point of view.

[0003] There are, however, issues related to handling data traffic such as XR traffic.BRIEF SUMMARY

[0004] This section is intended to include examples and is not intended to be limiting.

[0005] In an exemplary embodiment, a method is disclosed that includes receiving, by a policy control function in a cellular network, a message for policy authorization for a multiaccess protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one ormore Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0006] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0007] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0008] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the messagecomprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0009] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0010] In an exemplary embodiment, a method is disclosed that includes receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the trafficspecific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0011] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0012] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0013] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, at a session management function in a cellular network,one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0014] In another exemplary embodiment, an apparatus comprises means for performing: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0015] In an exemplary embodiment, a method is disclosed that includes receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for amulti-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0016] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0017] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributingby the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0018] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0019] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multiaccess protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multiaccess protocol data unit session.

[0020] In an exemplary embodiment, a method is disclosed that includes receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0021] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0022] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performancemeasurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0023] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0024] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multiaccess protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in atleast uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0025] In an exemplary embodiment, a method is disclosed that includes receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0026] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is thecomputer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0027] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multiaccess protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multiaccess protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0028] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of theprotocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multiaccess protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0029] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0030] In an exemplary embodiment, a method is disclosed that includes receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multiaccess protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0031] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0032] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause theapparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0033] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules;determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0034] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multiaccess protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0035] In an exemplary embodiment, a method is disclosed that includes receiving, by a user equipment connected to cellular network and from a user plane function in the cellularnetwork, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multiaccess protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0036] An additional exemplary embodiment includes a computer program, comprising instructions for performing the method of the previous paragraph, when the computer program is run on an apparatus. The computer program according to this paragraph, wherein the computer program is a computer program product comprising a computer-readable medium bearing the instructions embodied therein for use with the apparatus. Another example is the computer program according to this paragraph, wherein the program is directly loadable into an internal memory of the apparatus.

[0037] An exemplary apparatus includes one or more processors and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol dataunit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0038] An exemplary computer program product includes a computer-readable storage medium bearing instructions that, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to adetermination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0039] In another exemplary embodiment, an apparatus comprises means for performing: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In the attached drawings:

[0041] FIG. 1 is a logic flow diagram of an Embodiment 1 for PDU Set based QoS handling support in MA PDU sessions;

[0042] FIG. 2 is a logic flow diagram for Embodiment 2 for ATSSS handling of XR traffic based on PDU Set level ATSSS Measurements;

[0043] FIG. 3, split over FIGS. 3A and 3B, is a signaling diagram that illustrates how the logic flow diagrams of FIGS. 1 and 2 can be implemented;

[0044] FIG. 4 is a revised part of a table from Table 6.3.1 : “The PCC rule information in 5GC” from 3GPP TS 23.503;

[0045] FIG. 5 is a block diagram for non-roaming and roaming with local breakout architecture for ATSSS support; and

[0046] FIG. 6 is a block diagram of one possible and non-limiting exemplary system in which the exemplary embodiments may be practiced.DETAILED DESCRIPTION OF THE DRAWINGS

[0047] Abbreviations that may be found in the specification and / or the drawing figures are defined below, at the end of the detailed description section.

[0048] The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. All of the embodiments described in this Detailed Description are exemplary embodiments provided to enable persons skilled in the art to make or use the invention and not to limit the scope of the invention which is defined by the claims.

[0049] When more than one drawing reference numeral, word, or acronym is used within this description withand in general as used within this description, the “ / ” may be interpreted as “or”, “and”, or “both”. As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or,” mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0050] As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and / or “including”, when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0051] It is noted that capital and lowercase words or phrases are considered to be the same herein. For instance, the words Slice and slice are the same, as are the phrases Network Repository Function and network repository function.

[0052] Any flow diagram (such as FIGS. 1 and 2) or signaling diagram (such as FIG. 3) herein is considered to be a logic flow diagram, and illustrates the operation of an exemplary method, results of execution of computer program instructions embodied on a computer readable memory, functions performed by logic implemented in hardware, and / or interconnected means for performing functions in accordance with an exemplary embodiment. Block diagrams (such as FIGS. 5 and 6) also illustrate the operation of an exemplary method, results of execution of computer program instructions embodied on a computer readable memory, functions performed by logic implemented in hardware, and / or interconnected means for performing functions in accordance with an exemplary embodiment. For methods, flow diagrams, and signaling diagrams, the orders of method steps, blocks in the flow, or signaling are not critical and instead are examples.

[0053] The examples herein relate to certain technical areas. Introduction to these technical areas is presented now, then problems in the technical areas are described, then the examples are described.

[0054] As stated above, different media units for, e.g., XR traffic, may contribute differently to the user experience, even when they are within a single stream. Thus, the importance of these media units is not unique from a media layer point of view. To support the above integrated and differentiated transmission of media units (e.g., a frame or a video slice), a PDU (protocol data unit) Set concept is introduced to denote the collection of packets (i.e., a PDU) carrying a media unit (e.g., I-Frame or P-Frame of a video). The 5GC obtains the following information to support PDU Set level QoS handling.

[0055] 1) PDU Set information, including PDU Set Sequence Number, End PDU of the PDU Set, PDU Sequence Number within a PDU Set, PDU Set Size and PDU Set importance.

[0056] 2) PDU Set level QoS parameters. PDU Set Delay Budget (PSDB) and PDUSet Error Rate (PSER) are introduced to control the delay and error rate on PDU Set level instead of PDU level.

[0057] Since XR traffic requires high data rate and low latency, it is helpful to split the information between multiple paths, corresponding to accesses, each path carrying PDU setsand having a corresponding QoS. Those paths can be multi-access (MA), which means the XR traffic can be transported via an access using a non-3GPP access node (referred to as a non-3GPP access) and an access using a 3 GPP access node (referred to as a 3 GPP access). While these multiple accesses can help transport the large information for XR traffic, there are still issues in this area.

[0058] Additionally, 3 GPP has defined the following in normative specifications.

[0059] I) PDU Set QoS Parameters

[0060] As described in 3GPP TS 23.501, a PDU Set is comprised of one or more PDUs carrying an application layer payload such as a video frame or video slice. The PDU Set based QoS handling by the NG-RAN is determined by PDU Set QoS Parameters in the QoS profile of the QoS Flow (specified in 3GPP TS 23.501, clause 5.7.7) and PDU Set information provided by the PSA UPF via N3 / N9 interface as described in 3GPP TS 23.501 clause 5.37.5.2.

[0061] At least one PDU Set QoS parameter should be sent to the NG-RAN to enable PDU Set based QoS handling.

[0062] The following PDU Set QoS Parameters are specified:

[0063] 1) PDU Set Error Rate (PSER): - defines an upper bound for a rate of noncongestion related PDU Set losses.

[0064] 2) PDU Set Delay Budget (PSDB): - defines an upper bound for the delay that a PDU Set may experience for the transfer between the UE and the N6 termination point at the UPF, i.e., the duration between the reception time of the first PDU (at the N6 termination point for DL or the UE for uplink) and the time when all PDUs of a PDU Set have been successfully received (at the UE for DL or N6 termination point for uplink).

[0065] 3) PDU Set Integrated Handling Indicator (PSIHI): Indicates whether allPDUs of a PDU Set are needed by an application for the usage of the PDU Set.

[0066] For a given QoS Flow, the values of PSDB, PSER and PSIHI can be different for uplink and DL. The QoS Profile may include the PDU Set QoS Parameters described in this clause (see clause 5.7.1.2) for uplink and / or DL direction(s). The PCF determines the PDU Set QoS Parameters based on information provided by AF and / or local configuration. The PDU Set QoS parameters are sent to the SMF as part of a PCC rule. The SMF sends them to NG-RAN as part of the QoS Profile. If the NG-RAN receives PDU Set QoS Parameters, the NG-RANenables the PDU Set based QoS handling and applies PDU Set QoS Parameters as described in 3GPP TS 38.300, TS 38.413, and TS 38.331.

[0067] II) PDU Set Handling in 3 GPP network for XR Traffic

[0068] As described in 3 GPP TS 23.501, a PDU Set is comprised of one or more PDUs carrying an application layer payload such as a video frame or video slice. Specifically, clause 3.1 of 3GPP TS 23.501 V18.3.0 (2023-09) defines PDU Set as the following: “One or more PDUs carrying the payload of one unit of information generated at the application level (e.g. frame(s) or video slice(s) etc. for extended Reality (XR) Services). All the PDUs of a PDU set are transmitted within the same QoS Flow.” In this document any reference to 3GPP TS 23.501 is to 3GPP TS 23.501 V18.3.0 (2023-09). The PDU Set based QoS handling by an NG- RAN (a 3GPP access node) is determined by PDU Set QoS Parameters in the QoS profile of the QoS Flow (specified in 3GPP TS 23.501, clause 5.7.7) and PDU Set information provided by the PSA UPF via N3 / N9 interface as described in 3GPP TS 23.501 clause 5.37.5.2.

[0069] Differentiated QoS handling of downlink PDUs that belong to different types of PDU Sets (e.g., I-Frames and P-Frames) is performed by mapping PDU Sets from the same application service flow to the same QoS Flow and provide differentiated QoS handling based on the PDU Set Importance marking provided by the UPF in the PDU Set Information of downlink packets.

[0070] The PDU Set information sent to the NG-RAN in the GTP-U header comprises the following:

[0071] 1. PDU Set Sequence Number.

[0072] 2. Indication of End PDU of the PDU Set.

[0073] 3. PDU Sequence Number within a PDU Set.

[0074] 4. PDU Set Size in bytes.

[0075] 5. PDU Set Importance, which identifies the importance of a PDU Set within a QoS Flow.

[0076] III) ATSSS

[0077] The ATSSS feature of the 5GS enables selecting an access for transmission (referred to as steering), moving data traffic from one access to another (referred to as switching), or using multiple accesses simultaneously (referred to as splitting). As described in 3GPP TS 23.501, clause 5.32, with ATSSS, the UE and UPF support functionality to direct datatraffic across one 3GPP access and one non-3GPP access. The UE is simultaneously connected to both accesses via a Multi- Access (MA) PDU Session that terminates in one PSA UPF. Splitting steering and switching may be supported in the UE and the UPF via one or more steering modes / functionality including MPTCP functionality, MPQUIC Functionality, and ATSSS-LL functionality. MPQUIC means multipath QUIC, where QUIC is an encrypted connection-oriented protocol that operates at the Transport Layer, or Layer 4, in the OSI model. MPTCP and MPQUIC are considered “higher layer” steering functionalities and are governed by IETF standards (IETF RFC 8684 for MPTCP and IETF RFCs 9000 / 9001 / 9002 and multi-path extensions for MPQUIC). The ATSSS-LL is considered a lower layer functionality where the steering, switching, or splitting is not governed by a specific protocol other than 3 GPP specifications and implementation. ATSSS-LL applies to all types of data traffic, including TCP traffic, UDP traffic, Ethernet traffic, or the like.

[0078] Note: 3 GPP defines Access Steering, Switching and Splitting as the following:

[0079] 1) Access Traffic Steering: The procedure that selects an access network for a new data flow and transfers the traffic of this data flow over the selected access network.

[0080] 2) Access Traffic Switching: The procedure that moves all traffic of an ongoing data flow from one access network to another access network in a way that maintains the continuity of the data flow.

[0081] 3) Access Traffic Splitting: The procedure that splits the traffic of a data flow across multiple access networks. When traffic splitting is applied to a data flow, some traffic of the data flow is transferred via one access and some other traffic of the same data flow is transferred via another access.

[0082] For uplink traffic, the UE applies network-provided policy (e.g., ATSSS rules) and considers local conditions to decide how traffic is to be distributed across the two or mote access networks. The PSA UPF similarly applies network policy and feedback from the UE to decide how to distribute downlink traffic between the N3 / N9 tunnels associated with the two or more available access networks.

[0083] IV) ATSSS Rules

[0084] After the establishment of an MA PDU Session, the UE receives a prioritized list of ATSSS rules from the SMF. Each ATSSS rule contains an Access Selection Descriptor that contains the following components:

[0085] 1) A Steering Mode, which determines how the traffic of the matching SDF should be distributed across 3GPP and non-3GPP accesses. The following Steering Modes are supported:

[0086] a) Active- Standby: This steering mode is used to steer an SDF on one access(the active access), when this access is available, and to switch the SDF to the available other access (the standby access), when active access becomes unavailable. When the active access becomes available again, the SDF is switched back to this access. If the standby access is not defined, then the SDF is allowed on the active access and should not be transferred on another access.

[0087] b) Smallest Delay: This steering mode is used to steer an SDF to the access that is determined to have the smallest Round-Trip Time (RTT). As defined in clause 3GPP TS 23.501 clause 5.32.5, measurements may be obtained by the UE and UPF to determine the RTT over 3GPP access and over non-3GPP access. In addition, if one access becomes unavailable, all SDF traffic is switched to the other available access. This steering mode can be used for the Non- GBR SDF.

[0088] c) Load-Balancing: This steering mode is used to split an SDF across both accesses if both accesses are available. This steering mode contains the percentage of the SDF traffic that should be sent over 3GPP access and over non-3GPP access. Load-Balancing is applicable to non-GBR SDF. In addition, if one access becomes unavailable, all SDF traffic is switched to the other available access, as if the percentage of the SDF traffic transported via the available access was 100%.

[0089] d) Priority-based: This steering mode is used to steer all the traffic of an SDF to the high priority access, until this access is determined to be congested. In this case, the traffic of the SDF is sent also to the low priority access, i.e., the SDF traffic is split over the two accesses. In addition, when the high priority access becomes unavailable, all SDF traffic is switched to the low priority access. How the UE and UPF determine when congestion occurs on an access is implementation-dependent. This steering mode can be used for the non-GBR SDF.

[0090] e) Redundant (without Threshold Values): This steering mode is used to duplicate traffic of an SDF on both accesses if both accesses are available. A Primary Access (either 3 GPP access or non-3GPP access) may be provided to the UE in the ATSSS rules and to the UPF in the N4 rules. The N4 refers to the N4 interface that connects the UPF to the SMF. If a Primary Access is provided, UE and UPF send all data packets of the SDF on the Primary Access and may duplicate data packets of the SDF on the other access. How many and which data packets are duplicated by UE and UPF on the other access is based on implementation. If the Primary Access is not provided to UE and UPF, the UE and UPF send all data packets of the SDF on both accesses. This steering mode can be used for GBR and Non-GBR SDF.

[0091] 2) Threshold Values: One or more threshold values may be provided when theSteering Mode is Priority-based or when the Steering Mode is Load-Balancing with fixed split percentages (i.e., without the Autonomous load-balance indicator or UE assistance indicator). One threshold value may be provided when the Steering Mode is Redundant. A threshold value may be either a value for RTT or a value for Packet Loss Rate. The threshold values are applicable to both accesses and are applied by the UE and UPF.

[0092] V) Access Network Performance Measurements

[0093] When an MA PDU Session is established, the network may provide the UE with Measurement Assistance Information. This information assists the UE in determining which measurements shall be performed over both accesses, as well as whether measurement reports need to be sent to the network.

[0094] The QoS rules and the N4 rules provided by SMF to UE and to UPF respectively include information (e.g., packet filters containing the UDP port or the MAC address associated with a QoS Flow), which enables the UE and UPF to route an SMF message to a specific QoS Flow.

[0095] The UE and the UPF may need to perform access performance measurements (i.e., performance measurements on an access) to estimate the Round-Trip Time (RTT) and / or the Packet Loss Rate (PLR) that an SDF is expected to experience when transmitted on a certain access type. Based on these measurements and the provisioned ATSSS rules in the UE and N4 rules in the UPF, the UE and the UPF decide how to distribute the traffic of an SDF across the two accesses.

[0096] Now that an introduction to certain technical areas has been provided, a description of problems in these areas is presented. In Rel-18, PDU Set QoS handling of XR traffic only applies when NG-RAN access is used. There is no study performed in Rel-18 about how to enhance 5GS to better support the steering, switching, and splitting of XR traffic over a combination of 3GPP and non-3GPP accesses when PDU Set Based QoS handling is enabled. Also, there is no clear solution on how to enable policy control to support ATSSS handling with PDU Set based QoS.

[0097] The examples herein address at least the above problems. The examples propose an approach to support a PDU Set based QoS framework for an MA PDU Session.

[0098] The following are a few assumptions concerning the examples.

[0099] 1. A first assumption is that ATSSS steering functionalities are the same irrespective of the QoS framework, PDU Set QoS, or PDU based QoS framework, while steering modes could be enhanced.

[0100] 2. The next assumption behind the examples is that PDU Set QoS is enabled on at least one of the QoS flows within the MA PDU Session. For instance, one can have PDU Set QoS active on 3GPP access and normal QoS active on non-3GPP access.

[0101] In case the UE is connected to 5GC via non-3GPP access, this means that XRM traffic gets transmitted via the intermediate nodes in non-3GPP access and PDU Set QoS parameters may be used to support PDU Set based QoS handling in the non-3GPP intermediate nodes.

[0102] 3. A third assumption is the following. In case the UE is connected to 5GC via non-3GPP access, XRM traffic gets transmitted via the intermediate nodes in non-3GPP access and PDU Set QoS Parameters and PDU Set Information are used to support PDU Set based QoS handling in the non-3GPP intermediate nodes.

[0103] 4. As a fourth assumption, UPF or UE should be able to identify which PDUs belong to a PDU Set.

[0104] It is noted that the primary emphasis placed herein is on XR traffic. However, the examples can be applicable to any data traffic that uses an MA PDU session. The data traffic can include any type of data transferred via PDUs.

[0105] There are two main examples that are described herein: Embodiment 1 (“Embl”); and Embodiment 3 (“Emb2”). Other examples are possible.

[0106] Before proceeding with a description of these examples, terminology about the various flows involved in the signaling is described. The following flows are used.

[0107] 1) QoS Flows are between the UE and UPF. A QoS flow has a set of QoS parameters / characteristics.

[0108] 2) A service data flow (SDF) is an aggregate set of packet flows carried through the UPF that matches a service data flow template (from 3GPP TS 23.503).

[0109] 3) Service data flow template is the set of service data flow filters in a PCCRule or an application identifier in a PCC rule referring to an application detection filter in the SMF or in the UPF, required for defining a service data flow (from 3GPP TS 23.503).

[0110] SDFs are mapped to QoS flows at the UPF by Packet Detection Rules (PDRs). XR flow or XR traffic flow do not have a precise 3 GPP definition, but they are the PDUs sent by an application to support XR services.

[0111] In Embodiment 1, this concerns a PDU Set based QoS handling support in MA PDU sessions. FIG. l is a logic flow diagram of Embodiment 1. The blocks for the logic flow diagram are described now.

[0112] 101. A QoS Flow of an MA PDU session is not associated with a specific access.

[0113] 102. For a QoS Flow of an MA PDU session, either PDU Set based QoS or normal QoS handling applies, where normal QoS handling is per PDU instead of per PDU set.

[0114] 103. PDU Set based QoS handling for a QoS Flow of an MA PDU session is based on the same PDU Set QoS parameters and PDU Set Information as for a normal PDU session.

[0115] 104. The SMF sends PDU Set QoS Parameters in the QoS profile of the QoSFlow to all accesses of an MA PDU session applicable for the QoS Flow. In this case, however it is assumed that the PDUs within a given PDU Set are sent via the same access.

[0116] 105. When a QoS Flow applies to both accesses (or possibly more accesses) of an MA PDU Session, the Flow is PDU Set based handled when both (all) available accesses support PDU Set based handling. This shall ensure the PSDB or PSER can be properly enforced by the selected access (among the two / multiple accesses), when all the PDUs within the PDU Set are transmitted via the same access. This occurs because the PSDB or PSER assumes that the enforcement ranges from first PDU to last PDU of the PDU Set.

[0117] 106. If any access relevant for a QoS Flow does not support PDU Set based handling, the Flow is handled based on normal PDU based QoS flow framework and SMF, UPF and optionally PCF, NEF, AF are informed accordingly. This is the situation when PDU Set based handling is not supported in an access, which can be a 3GPP or a non-3GPP access. In this case, flow is handled with the existing QoS flow framework, including using Packet Delay Budget, Packet Error Rate, and the like. The UPF will then take this into account and the UE does not insert PDU Set marking information in the UP PDUs transmitted via the given access.

[0118] 107. If it is supported by the corresponding access path, UPF sends PDU Set marking Information in the UP PDUs to the corresponding accesses of an MA PDU session applicable for the QoS Flow, for instance the UPF may send PDU Set Information in GTP-U DL packets. It is noted that the term “access” is primarily used herein, but other terms such as “access path” or even “path” may be used and are considered to be equivalent to an “access”.

[0119] 108. QoS rules provided to the UE might include PDU Set QoS Parameters like the PSDB, the PSER, PSIHI. QoS rules provided via one access are valid for all accesses of the MA PDU session, thus it may be sufficient to provide the QoS rules once for a given MA PDU Session. The UE typically gets PDU Set QoS parameters via the control plane.

[0120] 109. Access Performance Measurements apply to a QoS Flow for which PDUSet based QoS handling applies. That is, as described both above and below (see signaling I l a and lb in FIG. 3), QoS performance measurements may be made for the non-3GPP access and for the 3GPP access, and these QoS performance measurements can be applied to a QoS Flow for which PDU Set based QoS applies.

[0121] 110. A UE may indicate its capability to support PDU Set based QoS framework in the uplink to handle PDU Set based QoS in an MA PDU Session establishment procedure. If this capability is supported, this is sent to the AMF so that a proper SMF supporting PDU Set QoS handling is selected. If it is not supported by the UE, SMF notifies PCF, NEF, AF that PDU Set based QoS handing shall not apply to the uplink direction.

[0122] 111. SMF, UPF, PCF may indicate their capability to each other to supportMA PDU sessions with ability to support PDU Set based QoS handling. This is to enable proper function selection. Discovery query parameters may be extended accordingly. It is possible this could be a pre-condition, meaning indicating this capability would be performed beforesupporting MA PDU sessions with ability to support PDU Set based QoS handling. It is also possible that other techniques are used.

[0123] Embodiment 2 is now described. This example concerns ATSSS handling of XR traffic based on PDU Set level ATSSS Measurements.

[0124] In Rel-18, ATSSS / N4 rules use RTT (Round-Trip-Delay) or Packet Loss Rate (PLR) threshold values for splitting, switching and steering the traffic flows at the UE and UPF.

[0125] This embodiment proposes to use PDU set QoS measurements in addition to existing measurements (e.g., RTT) in access performance measurements for the PDU Set based XR traffic flows. For instance, threshold values of actually incurred delay for transmitting a PDU Set (i.e., incurred PSD and PDU Set Loss Rate (PSLR) can be used for steering, switching and splitting of XR traffic flows). Note that PSD and PSLR are the actual incurred values and not same as the PDU Set QoS Parameters PSDB and PSER (which are more like threshold values). Consider the following detail:

[0126] 1. From the network side (e.g., AF), threshold values for PSDB, PSER andPSIHI are set for a PDU Set of the QoS flow. These thresholds are defined for the specific PDU Set. These values are static threshold values and valid / applicable from end-to-end (server to UE in downlink and UE to server for uplink traffic) transport of the PDU set.

[0127] 2. Now, this value can be provided / available / applicable to both the accesses.However, this is just for reference and the actual calculated / measurement value of the parameters are the PSLR (dynamic instantaneous / measurement value for PSER) and PSD (dynamic instantaneous / measurement value for PDB). For example, assume the set threshold PSER is 80% and the measured PSLR value may be 70% in 3GPP access leg / path and 90% in the non-3GPP access leg / path. A different parameter name is used to differentiate between the static threshold value (e.g., PSER) versus the measured dynamic value (e.g., PSLR).

[0128] 3. For PSIHI, there will not be any dynamic measured value, and instead will be the same static value only. This can be the same for both accesses. Hence, this may be skipped for differentiating between two accesses.

[0129] 4. ATSSS rules can be created by PCF / SMF for uplink (for UE) and N4 rules for DL (for UPF) to take split decision depending on the measured dynamic parameters either PSLR, or PSD, or PSLR+PSD (for example, PSLR of access 1 > PSLR of access 2, and PSD accessl > PSD_access2).

[0130] Additionally, PSLR is a quality of service parameter that is a real-time measured average value of PSER, which is a static quality of service parameter. The PSD is a quality of service parameter that is a real-time measured average value of PSDB, which is a static quality of service parameter.

[0131] In uplink, the UE can take PSD, PSLR related measurements as instructed by ATSSS rules (which may have threshold values of PSD and PSLR) and Measurement Assistance Information (Info) sent to the UE (as specified in 3GPP TS 23.501 section 5.32.5 and 5.32.8). Similarly, in DL, a UPF can make PDU Set related measurements (e.g., incurred values), and use them to determine splitting / switching / steering.

[0132] Access Nodes (e g., NG-RAN, N3IWF, TNGF, W-AGF) may take PDU Set related measurements and communicate the result to both the UE and the UPF to take the result into consideration when steering, switching, and / or splitting PDU Set based XR traffic flows.

[0133] The procedure in an example is described in FIG. 2, which is a logic flow diagram for Embodiment 2 for ATSSS handling of XR traffic based on PDU Set level ATSSS Measurements.

[0134] 201. PCF control of Access Traffic Steering, Switching and Splitting for a detected service data flow (SDF) is enabled by including Multi- Access PDU (MA PDU) Session Control information in a PCC rule. If dynamic PCC is to be used for the MA PDU Session, SMF receives the modified MA PDU Session control information for XR QoS flows from PCF. In an XR case, threshold values for PDU Set Loss Rate and PDU Set Delay can be sent in the MA PDU Session control information of the PCC rule.

[0135] 202. SMF maps these PCC rules to the following:

[0136] a) ATSSS rules, which are sent to the UE using NAS messages during PDU Session Establishment / Modification and applied by the UE to enforce ATSSS policy in the uplink traffic; or

[0137] b) N4 rules, which are sent to the UPF and applied to enforce the ATSSS policy for the DL traffic.

[0138] 203. The Traffic Descriptor in the ATSSS or MA (N4) rule is generated by theSMF from the SDF template of the PCC rule. For instance, the new rule can be: Steering Functionality can be MPTCP / MPQUIC / ATSSS-LL; and Steering Mode can be load balancing, priority-based, or redundant. It is noted that the SMF can send the rule(s) to the UE and UPF.

[0139] a) An example load balancing steering mode could include the following.

[0140] “Traffic Descriptor: RTP / SRTP”, “Steering Mode: Load-Balancing, 3GPP=20%, non-3GPP=80%, “Threshold Value for PDU Set Loss Rate = 5%”, “Steering Functionality: MPTCP”:

[0141] This rule can be interpreted as the following: “send 20% of the RTP traffic of Application-1 to 3GPP access and 80% to non-3GPP access, as long as the PDU Set Loss Rate does not exceed 5% on both accesses, by using the MPTCP functionality. If the measured PDU Set Loss Rate of an access exceeds 5%, then the UE and UPF may stop sending traffic on this access, or may continue sending traffic on this access but should reduce the traffic on this access by an implementation specific amount and shall send the amount of reduced traffic on the other access. When all measured parameters (i.e., PDU Set Delay and PDU Set Loss Rate) for both accesses do not exceed the provided threshold values, the UE and UPF shall apply the fixed split percentages”.

[0142] b) An example redundant steering mode could include the following.

[0143] “Traffic Descriptor: TCP”, “Steering Mode: Redundant, 3GPP=20%, non- 3GPP=80%, “Threshold Value for PDU Set Measured Delay = 5ms”, “Steering Functionality: MPQUIC”:

[0144] This rule can be interpreted as the following: “traffic duplication is applied to the TCP traffic. If the measured PDU Set Delay exceeds 5ms on both accesses, all matched traffic is duplicated and transmitted on both accesses. If the measured PDU Set Delay exceeds 5ms on one access only (either 3 GPP or non-3GPP access), all matched traffic is sent over the other access only. If the measured PDU Set Delay does not exceed 5ms on any access, the UE or UPF selects the access based on their own implementation, e.g., the access with lower PDU Set Loss Rate to transmit all matched traffic”.

[0145] c) An example priority-based steering mode could include the following.

[0146] The UE and the UPF use the maximum PDU Set Delay value or the maximum PDU Set Loss Rate value or both to detect when an access of an MA PDU session is congested. If the maximum PDU Set Delay value or the maximum PDU Set loss rate value in an access of the MA PDU session exceeds the indicated value, the UE and the UPF may send some traffic over the other access, i.e., the UE splits the SDF traffic over both the access with high priority and the access with low priority.

[0147] 204. Updated MA(or N4) rules are sent by the SMF or PCF (via SMF) to theUPF.

[0148] 205. Updated ATSSS rules are sent by the SMF or PCF (via SMF) to the UE.

[0149] 206. uplink data received by the UE from its higher (e.g., application layer) layers and sent to the application server. And, DL data sent from the application server towards the UE.

[0150] 207. The UE and UPF separately determine how to split the application traffic between 3GPP and non-3GPP access based on the received rules. Splitting is based on PDU Set QoS measurements and the split happens across PDU Set Boundaries. In other words, the UE (for uplink PDU Set) or the UPF (for the DL PDU Set) handle a PDU Set as a whole, i.e., they do not split a PDU Set to the different access. Instead, any need for access steering, switching, or splitting takes place at PDU Set boundaries, i.e., once an access has been selected for a PDU Set instance, that access may not be changed until the end of the current PDU Set instance. It can be changed only after transmitting all the PDUs of a given PDU Set. This makes it possible to enforce PDU Set QoS independently on each access.

[0151] 208. The UE and the UPF perform accessing performance measurements in order to estimate the PDU Set Loss Rate (PSLR) and / or the PDU Set Delay (PSD) that a PDU Set is expected to experience when transmitted on a certain access.

[0152] 209. Based on these measurements and the provisioned ATSSS rules in theUE and N4 rules in the UPF, the UE and the UPF decide how to distribute the traffic of an SDF across the two accesses. The N4 rules are also referred to as MAR rules, as a MAR rule is one type of N4 rule. Splitting is based on PDU Set QoS measurements and the split happens across PDU Set Boundaries. A PDU Set boundary is when one PDU set ends and another PDU set begins. Access should not be changed when transmission of PDUs within a PDU Set is ongoing. Thus, the UE and UPF change the access only at PDU Set boundaries as determined in block 207.

[0153] As mentioned in 3GPP TS 23.501, section 5.32.3, Policy for ATSSS Control, “If dynamic PCC is to be used for the MA PDU Session, the PCF may take ATSSS policy decisions and create PCC rules that contain MA PDU Session Control information, (as specified in 3GPP TS 23.503

[0045] ), which determines how the uplink and the downlink traffic of the MAPDU Session should be distributed across the 3GPP and non-3GPP accesses. If dynamic PCC is not deployed, local policy in SMF is used.”

[0154] FIG. 3 is a signaling diagram that illustrates how the logic flow diagrams of FIGS. 1 and 2 can be implemented. That is, this illustrates both Embodiment 1 and Embodiment 2. FIG. 3 has the following entities: UE 10; non-3GPP access node (n3GPP access node) 310; 3GPP access node 70; UPF 99-1, SMF 99-2, PCF 99-3; NEF 99-4; and AF 99-5. Network functions (NFs) use the reference number 99 and are further described in part in reference to FIG. 6, and individual NFs are described now. The user plane function (UPF) 99-1 is a first network function, and is a network function that plays a critical role in data transfer. It interconnects the Data Network (DN) in the 5G architecture. The UPF 99-1 is also responsible for packet routing and forwarding, packet inspections, QoS (Quality of Service) handling, and being an anchor point for intra and inter-RAT mobility. For more information, see 3GPP TS 23.501, §6.2.3. The session management function (SMF) 99-2 is a 5G core component that performs a fundamental role in the 5G Service-Based Architecture (SBA). The SMF is primarily responsible for interacting with the decoupled data plane, creating, updating and removing Protocol Data Unit (PDU) sessions and managing session context with the User Plane Function (UPF). For further information, see 3GPP TS 23.501, §6.2.2. The policy control function (PCF) 99-3 has at least the functions: supports unified policy framework to govern network behavior; and provides policy rules to control plane function(s) to enforce them. AF 99-5 interacts with the 3GPP Core Network in order to provide services. For more detail, see 3GPP TS 23.501, §6.2.10. The network exposure function (NEF) 99-4 provides a platform for creating new services by consolidating APIs and presenting unified access to the API framework for developers. For additional information, see 3GPP TS 23.501, §6.2.5.

[0155] FIG. 3 is split over FIGS. 3 A and 3B. FIG. 3 A involves block 1 to signaling 9, and FIG. 3B involves signaling 10 to 13b. Steps 4-9 are based on a PDU Session Modification procedure 320, which has been modified for the examples herein. This figure describes Embodiment 2 in certain blocks and signaling, but Embodiment 1 is also described separately from those blocks and signaling.

[0156] Block 1. This is an MA PDU Session establishment procedure and involves the UE 10, n3GPP (non-3GPP) access node 310, 3GPP access node 70, UPF 99-1, and SMF 99- 2. The UE may indicate to the SMF its capability to support PDU Set based QoS framework inthe uplink, e.g., in an MA PDU Session establishment request. Note this may be supported using the existing UE 5GSM core network capability signaling.

[0157] Signaling 2. The AF 99-5 requests PDU Set QoS in the XR Flow Description and may provide PDU Set QoS Parameters in the same way as for a normal PDU Session. PDU Set QoS Parameters may comprise one or more of the existing PSDB, PSER, PSIHI. This occurs via an Nnef_AFSessionWithQoS Create / Update (create or update message, where one of these is chosen), where the parameters are PDU Set QoS Parameters. The Nnef is a service-based interface exhibited by the NEF.

[0158] Signaling 3. The NEF 99-4 sends a message of Npcf PolicyAuthorization Create / Update with the parameters of PDU Set QoS Parameters. The Npcf is a service-based interface exhibited by the PCF. For Embodiment 1 (Emb 1),

[0159] Block 4 and signaling 4a. The PCF 99-3 generates (see block 4) PCC rule(s) 340 based on the information from the AF and / or local configuration. MA PDU Session Control Information of PCC rules 140 will be modified for PDU Set specific traffic. New measurements should be supported for PDU Set specific traffic, and relevant threshold(s) should be generated (block 4) and provided (signaling 4a) in the PCC rules 140 as shown in the table of FIG. 4 (as one example). Table 4 is a revised part of a table from Table 6.3.1 : “The PCC rule information in 5GC” from 3GPP TS 23.503. As indicated by reference 410, this adds the following description to the information name of Threshold Values: “A Maximum threshold value for PDU Set Loss Rate (PSLR) or PDU Set Delay (PSD) for XR traffic if PDU Set QoS is supported in PCC rules”. Note the PCF may also trigger setup of PDU Set QoS (based on the AF request). There may be a maximum threshold values for one of PSLR or PSD, or there could be two maximum threshold values for both PSLR and PSD. For Embodiment 1, the updated MA PDU session control information can include (see reference 330, which is indication of the rules) PCC rules for an uplink or DL MA PDU session comprising one or more of PSDB, PSER, or PSIHI measurements. Furthermore, the PCC rules 340 for Embodiment 1 can include the rule 335 that if PDU set handling is not supported by both accesses, then normal PDU handling and rules shall be used, means normal QoS handling is per PDU instead of per PDU Set, and normal ATSSS and N4 (e.g., session) rules that do not involve PDU Sets are used. That is, PDU based flow framework should be used to handle PDUs instead of PDU sets and to apply rules that do not involve PDU Sets

[0160] Note that PCC rules 340 can include both rules for uplink (for the UE) and for DL (for the UPF). Since the uplink and DL rules are sent to two different entities, if rules are generated and sent for both uplink and DL, there would be PCC rule(s) for the uplink MA PDU session and PCC rule(s) for the DL MA PDU session.

[0161] Block 5. The SMF 99-2 determines to activate ATSSS / N4 rules based on PDU Set QoS measurements and to activate PDU Set based QoS as specified in the PCC rules. The SMF 99-2 generates ATSSS and N4 rules for the UE and UPF respectively, including the new thresholds PSLR, PSD and instructions for PDU Set related measurements. Specifically, the SMF enables ATSSS / N4 rules [Emb 2, Embodiment 2]: to use PSLR, PSD thresholds to split and steer the PDU Set traffic across multiple accesses. It is note that PDU Set traffic may be referred to as traffic specific to protocol data unit sets.

[0162] Signaling 6a and 6b. The SMF 99-2 sends an updated QoS Profile message specifying PDU Set QoS (if needed) to the NG-RAN (see signaling 6a) and a NAS message specifying PDU Set measurement based ATSSS rules to the UE (see signaling 6b). The modified ATSSS rules with PSLR, PSD thresholds are sent in signaling 6b for Embodiment 2. For Embodiment 1, the rules 330 and 335 are indicated in the modified ATSSS rules. Note that the modified ATSSS rules may also flow through signaling 6a.

[0163] Note in general for a QoS Flow of an MA PDU session, either PDU Set based QoS or normal QoS handling (e.g., QoS for PDUs not part of a PDU Set) should apply. However, PDU Set Based measurements for ATSSS are possible when PDU Set QoS is active for both accesses. The SMF determines if PDU Set based or normal QoS applies based on PCC rules provided by the PCF (e.g., based on the request from the AF) and / or local configuration. When the SMF decides that PDU Set based QoS is to apply, the SMF:

[0164] 1) sends PDU Set QoS Parameters in the QoS profile of the QoS Flow to the3 GPP access of the MA PDU session, and

[0165] 2) sends PDU Set QoS Parameters in the QoS profile of the QoS Flow to the non-3GPP access of the MA PDU session.

[0166] The PDU Set QoS parameters for QoS flows of an MA PDU session may be the same as for the single PDU Session, i.e., PSDB, PSER, PSIHI.

[0167] In signaling 6b, the new ATSSS rules and optionally QoS rules are sent to the UE by 3GPP access. However, either access could be used. That is, QoS rules provided via oneaccess are valid for all accesses of the MA PDU session. The rules might include threshold values applicable for PSD, PSER and the request to perform the new measurements related to flows for which PDU Set based QoS apply.

[0168] Signaling 7: The QoS profile with PDU Set QoS Parameters are sent to the non-3GPP access. Note that this can include one or more of PDU set specific delay (PSDB), PDU set error rate (PSER), or PDU set Importance (PSIHI) measurements.

[0169] Signaling 8a: NG-RAN (the 3GPP access node 70) replies to the request from the SMF and indicates if the NG-RAN’ s and UE’s NAS message in 6a was successful.

[0170] Signaling 8b: The intermediate non-3GPP access node 310 (e.g., N3IWF / TNGF / W-AGF) replies to the request (from step 7) from the SMF and indicates if the request was successful.

[0171] Signaling 9. If the signaling in 8a / 8b is successful, the SMF 99-2 transfers the new N4 rules to the UPF. The new N4 rules are the modified N4 rules with PSLR, PSD thresholds for Embodiment 2. For Embodiment 1, the rules 330 and 335 are indicated in the modified N4 rules. The SMF also activates PDU Set marking (e.g., to be used by the UPF to mark PDU Sets accordingly).

[0172] Signaling 10. Uplink and downlink traffic is exchanged between the AF 99-5 and the UPF 99-1.

[0173] The UPF sends PDU Set Information to the GTP-U header of DL traffic to both tunnels connecting the UPF to the 3 GPP and the non-3GPP access (or all accesses in any future ATSSS extension that includes more than two accesses).

[0174] Signaling I la and 11b. Existing Performance Measurements apply to a QoS Flow for which PDU Set based QoS handling applies, too. For those flows, extra measurements based on PSD, PSER may also take place at the UE and the UPF.

[0175] Blocks 12a and 12b. Based on these measurements (including the new measurements) and the provisioned ATSSS rules in the UE and N4 rules in the UPF, the UE and the UPF decide how to (re)distribute (e.g., split and steer) the traffic of an SDF across the two accesses. The (re)distributing downlink or uplink data traffic may use the one or more estimated PSLR or PSD in conjunction with one or more thresholds, e.g., for Embodiment 2.

[0176] The UE and the UPF handle a PDU Set as a whole, i.e., they do not split a PDU Set to the different access. That is, any need for access switching / splitting takes place atPDU Set boundaries. The PSDB would not be properly enforced otherwise, as the PSDB assumes that the enforcement ranges from first PDU to last PDU of the PDU Set.

[0177] Signaling 13a and 13b. These are representations of the UPF 99-1 redistributing DL flows based on adjusting DL traffic between 3GPP access (13a) and n3GPP access (13b), and the UE 10 redistributing uplink flows based on adjusting uplink traffic between 3GPP access (13a) and n3GPP access (13b). Reference 330 shows that flows can be redistributed for Access 1, which is through one of n-3GPP access or 3 GPP access, and Access2, which is through the other of n-3GPP access or 3GPP access.

[0178] The examples provide generic techniques that are applicable for all the following scenarios:

[0179] 1. Two 3GPP accesses (e g., NR and NR);

[0180] 2. A 3 GPP access and a non-3GPP access; or

[0181] 3. Two non-3GPP accesses.

[0182] Non-3GPP access may include one or more of the following:

[0183] 1. Untrusted non-3GPP access (N3IWF);

[0184] 2. Trusted non-3GPP access (TNGF);

[0185] 3. Wireline access, where Wireline access may be a Wireline 5G CableAccess Network or a Wireline BBF Access Network (W-AGF); or

[0186] 4. WLAN access.

[0187] Referring to FIG. 5, this figure illustrates one possible example of an architecture 500 that can be used for the examples herein. FIG. 5 is a block diagram corresponding to Figure 4.2.10-1, “Non-roaming and Roaming with Local Breakout architecture for ATSSS support” from 3GPP TS 23.501. This is a revised version, however. The UE 10 communicates with the AMF 99-6 through both the 3 GPP access 510 (via a 3 GPP access node 70) and the non-3GPP access 520 (via a non-3GPP access node 310). Both accesses use the N1 reference point, which is a reference point between the UE and the AMF. Both the 3 GPP access 510 and the non-3GPP access 520 may also communicate with the AMF 99-6 via the N2 reference point, which is a reference point between the (R)AN (radio access network or access network) and the AMF. The AMF receives all connection and session related information from the UE (using the N1 / N2 reference points) and is responsible for handling connection and mobility management tasks.

[0188] This architecture 500 also includes an SMF 99-2, PCF 99-3, data network 91, and UPF, and the various reference points between these entities are also shown. The UE 10 includes the following: MPTCP functionality 530-1; MPQUIC functionality 540-1; ATSSS-LL functionality 550-1; and PMF 560-1. The UPF 99-1 is structured similarly, comprising the following: MPTCP functionality 530-2; MPQUIC functionality 540-2; ATSSS-UU functionality 550-2; and PMF 560-2.

[0189] Turning to FIG. 6, this figure shows a block diagram of one possible and nonlimiting example of a cellular network 1 that is connected to a user equipment (UE) 10 and to a data network 91. A number of network elements are shown in the cellular network of FIG. 6: a 3GPP access node 70; a non-3GPP access node 310; and a core network 90 including network functions (NFs) 99.

[0190] In FIG. 6, a user equipment (UE) 10 is in wireless communication via radio link 11 with the 3 GPP access node 70 of the cellular network 1. A UE 10 is a wireless communication device, such as a mobile device, that is configured to access a cellular network. The UE 10 is illustrated with one or more antennas 28. The ellipses 2 indicate there could be multiple UEs 10 in wireless communication via radio links with the 3GPP access node 70. The UE 10 includes one or more processors 13, one or more memories 15, and other circuitry 16. The other circuitry 16 includes one or more receivers (Rx(s)) 17 and one or more transmitters (Tx(s)) 18. A program 12 is used to cause the UE 10 to perform the operations described herein. For a UE 10, the other circuitry 16 could include circuitry such as for user interface elements (not shown) like a display.

[0191] The 3GPP access node 70, as a network element of the cellular network 1, provides the UE 10 access to cellular network 1 and to the data network 91 via the core network 90 (e.g., via a user plane function (UPF) of the core network 90). The 3GPP access node 70 is illustrated as having one or more antennas 58. In general, the 3GPP access node 70 may be a base station, commonly referred to as RAN node 70, although many will make reference to this as a gNB (gNode B, a base station for NR, new radio) instead. There are, however, many other examples of RAN nodes including an eNB (evolved Node B) or TRP (Transmission-Reception Point). The 3GPP access node 70 includes one or more processors 73, one or more memories 75, and other circuitry 76. The other circuitry 76 includes one or more receivers (Rx(s)) 77 and oneor more transmiters (Tx(s)) 78. A program 72 is used to cause the 3GPP access node 70 to perform the operations described herein.

[0192] Two or more 3GPP access nodes 70 communicate using, e.g., link(s) 79. The link(s) 79 may be wired or wireless or both and may implement, e.g., an Xn interface for 5G (fifth generation), an X2 interface for LTE (Long Term Evolution), or other suitable interface for other standards.

[0193] The non-3GPP access node 310 is assumed to be structured similarly to the 3GPP access node 70 in terms of circuitry. The UE 10 communicates with the non-3GPP access node 310 using a wireless link 11-2, and the 3 GPP access node 310 uses a link 32 to communicate with the core network 90 and the AMF 99-6.

[0194] The cellular network 1 may include a core network 90, as a second network element or elements, that may include core network functionality, and which provide connectivity via a link or links 81 with a data network 91, such as a telephone network and / or a data communications network (e.g., the Internet). The core network 90 includes one or more processors 93, one or more memories 95, and other circuitry 96. The other circuitry 96 includes one or more receivers (Rx(s)) 97 and one or more transmiters (Tx(s)) 98. A program 92 is used to cause the core network 90 to perform the operations described herein.

[0195] The core network 90 could be a 5GC (5G core network). The core network 90 can implement or comprise multiple network functions (NF(s)) 99, and the program 92 may comprise one or more of the NFs 99. A 5G core network may use hardware such as memory and processors and a virtualization layer. It could be a single standalone computing system, a distributed computing system, or a cloud computing system. The NFs 99, as network elements, of the core network could be containers or virtual machines running on the hardware of the computing system(s) making up the core network 90.

[0196] The NFs 99 of the following have already been described and used: UPF 99- 1; SMF 99-2; PCF 99-3; AF 99-4; NEF 99-5; and AMF 99-6. Core network functionality for access and mobility management in an LTE (Long Term Evolution) network may be provided by an MME (Mobility Management Entity) and / or SGW (Serving Gateway) functionality, which routes data to the data network. Many others are possible, as illustrated by the examples in FIG. 6: MME; SGW; GMLC (Gateway Mobile Location Center); LMF (Location ManagementFunction); UDM (Unified Data Management) / UDR (Unified Data Repository); NRF (NetworkRepository Function); and / or E-SMLC (Evolved Serving Mobile Location Center). These are merely exemplary core network functionality that may be provided by the core network 90, and note that both 5G and LTE core network functionality might be provided by the core network 90. The 3GPP access node 70 is coupled via a backhaul link 31 to the core network 90 and the non- 3GPP access node 310 is coupled to the core network 90 (e.g., and to the AMF 99-6) via the link 32. The 3GPP access node 70 and the core network 90 may include an NG (Next Generation) interface for 5G, or an SI interface for LTE, or other suitable interface for other radio access technologies for communicating via the backhaul link 31.

[0197] In the data network 91, there is a computer-readable medium 94. The computer-readable medium 94 contains instructions that, when downloaded and installed into the memories 15, 75, or 95 of the corresponding UE 10, 3GPP access node 70, and / or core network element(s) 90, and executed by processor(s) 13, 73, or 93, cause the respective device to perform corresponding actions described herein. The computer-readable medium 94 may be implemented in other forms, such as via a compact disc or memory stick.

[0198] The programs 12, 72, and 92 contain instructions stored by corresponding one or more memories 15, 75, or 95. These instructions, when executed by the corresponding one or more processors 13, 73, or 93, cause the corresponding apparatus 10, 70, or 90, to perform the operations described herein. The computer readable memories 15, 75, or 95 are circuitry and may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, firmware, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The computer readable memories 15, 75, and 95 may be means for performing storage functions. The processors 13, 73, and 93, are circuitry and may be of any type suitable to the local technical environment. For example, these processors may include one or more of general-purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), processors based on a multi-core processor architecture, and may also include specialized circuits such as field-programmable gate arrays (FPGAs), application specific circuits (ASICs), signal processing devices and other devices, or combinations of these devices, as non-limiting examples. The processors 13, 73, and 93 may be means for causing their respective apparatus to perform functions, such as those described herein. Particularly, for any apparatus having means to perform functions described herein, themeans may include at least one processor, and at least one memory storing instructions that, when executed by at least one processor, cause the performance of the apparatus.

[0199] The receivers 17, 77, and 97, and the transmitters 18, 78, and 98 may implement wired or wireless interfaces. The receivers and transmitters may be grouped together as transceivers.

[0200] In general, the various embodiments of the user equipment 10 can include, but are not limited to, cellular telephones (such as smart phones, mobile phones, cellular phones, voice over Internet Protocol (IP) (VoIP) phones, and / or wireless local loop phones), tablets, portable computers, vehicles or vehicle-mounted devices for, e.g., wireless V2X (vehicle-to- everything) communication, image capture devices such as digital cameras, gaming devices, music storage and playback appliances, Internet appliances (including Internet of Things, loT, devices), loT devices with sensors and / or actuators for, e.g., automation applications, as well as portable units or terminals that incorporate combinations of such functions, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), Universal Serial Bus (USB) dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. That is, the UE 10 could be any end device that may be capable of wireless communication. By way of example rather than limitation, the UE may also be referred to as a communication device, terminal device (MT), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT).

[0201] Without in any way limiting the scope, interpretation, or application of the claims appearing below, a technical effect and / or advantage of one or more of the example embodiments disclosed herein is better QoS for XR traffic. Another technical effect and / or advantage of one or more of the example embodiments disclosed herein is better allocation of 3GPP and non-3GPP access resources for transmission of XR traffic. Another technical effect and / or advantage of one or more of the example embodiments disclosed herein is application aware access resource allocation. A further technical effect and / or advantage of one or more ofthe example embodiments disclosed herein is access performance (e.g., RTT, PLR) aware allocation of access resources to PDU Sets.

[0202] The following are additional examples.

[0203] Example 1. A method, comprising: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0204] Example 2. The method according to example 1, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

[0205] Example 3. The method according to any of examples 1 or 2, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or more thresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

[0206] Example 4. The method according to any of examples 1 to 3, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or a downlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session and one or more policy and charging control rules for the downlink multiple access protocol data unit session.

[0207] Example 5. A method, comprising: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol dataunit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multiaccess protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0208] Example 6. The method according to example 5, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

[0209] Example 7. The method according to example 5, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flow template of one of the one or more policy and charging control rules and indicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

[0210] Example 8. The method according to any of examples 5 to 7, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

[0211] Example 9. The method according to any of examples 5 to 8, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific userequipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

[0212] Example 10. The method according to any of examples 5 to 9, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0213] Example 11. A method, comprising: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0214] Example 12. The method according to example 11, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0215] Example 13. The method according to example 12, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0216] Example 14. The method according to any of examples 11 to 13, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0217] Example 15. The method according to example 14, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and theredistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0218] Example 16. A method, comprising: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multiaccess protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multiaccess protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0219] Example 17. The method according to example 16, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0220] Example 18. The method according to example 17, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0221] Example 19. The method according to any of examples 16 to 18, further comprising, prior to the receiving, sending from the user equipment to at least a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

[0222] Example 20. The method according to any of examples 16 to 19, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0223] Example 21. The method according to example 20, wherein performing performance measurements comprises accessing performance measurements in order to estimateone or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0224] Example 22. A method, comprising: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0225] Example 23. The method according to example 22, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses doesnot support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multiaccess protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0226] Example 24. The method according to any of examples 22 to 23, further comprising sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprising one or more of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

[0227] Example 25. The method according to any of examples 22 to 24, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a static quality of service parameter and the PSD is a quality of service parameter that is a realtime measured average value of PSDB that is a static quality of service parameter.

[0228] Example 26. The method according to any of examples 22 to 25, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

[0229] Example 27. The method according to any of examples 22 to 26, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0230] Example 28. A method, comprising: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-accessprotocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0231] Example 29. The method according to example 28, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0232] Example 30. The method according to any of examples 28 to 29, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0233] Example 31. The method according to example 30, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0234] Example 32. A method, comprising: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multiaccess protocol data unit session for data traffic communicated over multiple accesses between auser equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0235] Example 33. The method according to example 32, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0236] Example 34. The method according to any of examples 32 to 33, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0237] Example 35. The method according to example 34, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0238] Example 36. The method according to any of examples 1 to 35, wherein the data traffic comprises traffic for extended reality.

[0239] Example 37. A computer program, comprising instructions for performing the methods of any of examples 1 to 36, when the computer program is run on an apparatus.

[0240] Example 38. The computer program according to example 37, wherein the computer program is a computer program product comprising a computer-readable medium bearing instructions embodied therein for use with the apparatus.

[0241] Example 39. The computer program according to example 37, wherein the computer program is directly loadable into an internal memory of the apparatus.

[0242] Example 40. An apparatus, comprising means for performing: receiving, by a policy control function in a cellular network, a message for policy authorization for a multiaccess protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0243] Example 41. The apparatus according to example 40, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

[0244] Example 42. The apparatus according to any of examples 40 or 41, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or more thresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

[0245] Example 43. The apparatus according to any of examples 40 to 42, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or a downlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session andone or more policy and charging control rules for the downlink multiple access protocol data unit session.

[0246] Example 44. An apparatus, comprising means for performing: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0247] Example 45. The apparatus according to example 44, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

[0248] Example 46. The apparatus according to example 44, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flow template of one of the one or more policy and charging control rules and indicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

[0249] Example 47. The apparatus according to any of examples 44 to 46, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

[0250] Example 48. The apparatus according to any of examples 44 to 47, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific user equipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

[0251] Example 49. The apparatus according to any of examples 44 to 48, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0252] Example 50. An apparatus, comprising means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0253] Example 51. The apparatus according to example 50, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0254] Example 52. The apparatus according to example 51, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0255] Example 53. The apparatus according to any of examples 50 to 52, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0256] Example 54. The apparatus according to example 53, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0257] Example 55. An apparatus, comprising means for performing: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0258] Example 56. The apparatus according to example 55, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0259] Example 57. The apparatus according to example 56, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0260] Example 58. The apparatus according to any of examples 55 to 57, wherein the means are further configured for performing, prior to the receiving, sending from the user equipment to at least a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

[0261] Example 59. The apparatus according to any of examples 55 to 58, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place atprotocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0262] Example 60. The apparatus according to example 59, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0263] Example 61. An apparatus, comprising means for performing: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multiaccess protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0264] Example 62. The apparatus according to example 61, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unitsets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multiaccess protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0265] Example 63. The apparatus according to any of examples 61 to 62, wherein the means are further configured for performing sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprising one or more of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

[0266] Example 64. The apparatus according to any of examples 61 to 63, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a static quality of service parameter and the PSD is a quality of service parameter that is a real-time measured average value of PSDB that is a static quality of service parameter.

[0267] Example 65. The apparatus according to any of examples 61 to 64, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

[0268] Example 66. The apparatus according to any of examples 61 to 65, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0269] Example 67. An apparatus, comprising means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellularnetwork, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multiaccess protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0270] Example 68. The apparatus according to example 67, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0271] Example 69. The apparatus according to any of examples 67 to 68, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0272] Example 70. The apparatus according to example 69, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0273] Example 71. An apparatus, comprising means for performing: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multiaccess protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0274] Example 72. The apparatus according to example 71, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0275] Example 73. The apparatus according to any of examples 71 to 72, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0276] Example 74. The apparatus according to example 73, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0277] Example 75. The apparatus according to any of examples 40 to 73, wherein the data traffic comprises traffic for extended reality.

[0278] Example 76. The apparatus according to any preceding apparatus example, wherein the means comprises: at least one processor; and at least one memory storing instructions that, when executed by at least one processor, cause the performance of the apparatus.

[0279] Example 77. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

[0280] Example 78. The apparatus according to example 77, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

[0281] Example 79. The apparatus according to any of examples 77 or 78, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or morethresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

[0282] Example 80. The apparatus according to any of examples 77 to 79, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or a downlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session and one or more policy and charging control rules for the downlink multiple access protocol data unit session.

[0283] Example 81. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

[0284] Example 82. The apparatus according to example 81, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

[0285] Example 83. The apparatus according to example 81, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flow template of one of the one or more policy and charging control rules andindicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

[0286] Example 84. The apparatus according to any of examples 81 to 83, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

[0287] Example 85. The apparatus according to any of examples 81 to 84, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific user equipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

[0288] Example 86. The apparatus according to any of examples 81 to 85, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0289] Example 87. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

[0290] Example 88. The apparatus according to example 87, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0291] Example 89. The apparatus according to example 88, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0292] Example 90. The apparatus according to any of examples 87 to 89, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0293] Example 91. The apparatus according to example 90, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0294] Example 92. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

[0295] Example 93. The apparatus according to example 92, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0296] Example 94. The apparatus according to example 93, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0297] Example 95. The apparatus according to any of examples 92 to 94, wherein the one or more memories further store instructions that, when executed by the one or more processors, cause the apparatus at least to perform, prior to the receiving, sending from the user equipment to at least a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

[0298] Example 96. The apparatus according to any of examples 92 to 95, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

[0299] Example 97. The apparatus according to example 96, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

[0300] Example 98. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multiaccess protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be usedalong with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multiaccess protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

[0301] Example 99. The apparatus according to example 98, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multiaccess protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0302] Example 100. The apparatus according to any of examples 98 to 99, wherein the one or more memories further store instructions that, when executed by the one or more processors, cause the apparatus at least to perform sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprisingone or more of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

[0303] Example 101. The apparatus according to any of examples 98 to 100, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a static quality of service parameter and the PSD is a quality of service parameter that is a real-time measured average value of PSDB that is a static quality of service parameter.

[0304] Example 102. The apparatus according to any of examples 98 to 101, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

[0305] Example 103. The apparatus according to any of examples 98 to 102, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

[0306] Example 104. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol dataunit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0307] Example 105. The apparatus according to example 104, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0308] Example 106. The apparatus according to any of examples 104 to 105, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0309] Example 107. The apparatus according to example 106, wherein the non- 3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0310] Example 108. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink forthe multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

[0311] Example 109. The apparatus according to example 108, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

[0312] Example 110. The apparatus according to any of examples 108 to 109, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

[0313] Example 111. The apparatus according to example 110, wherein the non- 3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

[0314] Example 112. The apparatus according to any of examples 77 to 111, wherein the data traffic comprises traffic for extended reality.

[0315] As used in this application, the term “circuitry” may refer to one or more or all of the following:

[0316] (a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and

[0317] (b) combinations of hardware circuits and software, such as (as applicable): (i) a combination of analog and / or digital hardware circuit(s) with software / firmware and (ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

[0318] (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0319] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0320] Embodiments herein may be implemented in software (executed by one or more processors), hardware (e.g., an application specific integrated circuit), or a combination of software and hardware. In an example embodiment, the software (e.g., application logic, an instruction set) is maintained on any one of various conventional computer-readable media. In the context of this document, a “computer-readable medium” may be any media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer, with one example of a computer described and depicted, e.g., in FIG. 5. A computer-readable medium may comprise a computer-readable storage medium (e.g., memories 15, 75, and 95 or other device) that may be any media or means that can contain, store, and / or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer. A computer-readable storage medium does not comprise propagating signals, and therefore may be considered to be non-transitory. The term “non-transitory”, as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM, random access memory, versus ROM, readonly memory).

[0321] If desired, the different functions discussed herein may be performed in a different order and / or concurrently with each other. Furthermore, if desired, one or more of the above-described functions may be optional or may be combined.

[0322] Although various aspects of the invention are set out in the independent claims, other aspects of the invention comprise other combinations of features from the described embodiments and / or the dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the claims.

[0323] It is also noted herein that while the above describes example embodiments of the invention, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.

[0324] The following abbreviations that may be found in the specification and / or the drawing figures are defined as follows:

[0325] 3 GPP third generation partnership project

[0326] 5G fifth generation

[0327] 5GC 5G core (network)

[0328] 5GS 5G system

[0329] 5GSM A layer in the core network that handles all the procedures for PDN

[0330] AF application function

[0331] AMF access and mobility management function

[0332] ATSSS Access Traffic Steering, Switching and Splitting

[0333] ATSSS-LL ATSSS-lower layer

[0334] BBF Broadband forum

[0335] E-SMLC evolved serving mobile location center

[0336] GMLC Gateway Mobile Location Center

[0337] eNB (or eNodeB) evolved Node B (e.g., an LTE base station)

[0338] GBR Guaranteed Bit Rate

[0339] GPRS General Packet Radio Service

[0340] GTP GPRS Tunneling Protocol

[0341] GTP-U GPRS Tunneling Protocol in User Plane

[0342] gNB (or gNodeB) base station for 5G / NR

[0343] I / F interface

[0344] info information

[0345] KI key issue

[0346] L4S Low Latency, Low Loss and Scalable Throughput

[0347] LMF Location Management Function

[0348] LTE long term evolution

[0349] MA multi-access

[0350] MAC medium access control

[0351] MAR Multi-access rule

[0352] MME mobility management entity

[0353] MPTCP Multipath TCP (transmission control protocol)

[0354] MPQUIC Multipath QUIC

[0355] n3GPP non-3GPP

[0356] NAS Non-access stratum

[0357] N3IWF Non-3GPP Inter-Working Function

[0358] NF network function

[0359] ng or NG next generation

[0360] NG-RAN next generation-radio access network

[0361] NR new radio

[0362] NRF Network Repository Function

[0363] N / W or NW network

[0364] OSI model Open System Interconnection (model)

[0365] PCC Policy and Charging Control

[0366] PCF Policy Control Function

[0367] PDN Packet Data Network

[0368] PDU protocol data unit

[0369] PDR Packet Detection Rule

[0370] PLR packet loss rate

[0371] PSA PDU Session Anchor

[0372] PSD PDU Set Delay

[0373] PSDB PDU Set Delay Budget

[0374] PSER PDU Set Error Rate

[0375] PSLR PDU Set Loss Rate

[0376] PSIHI PDU Set Integrated Handling Indicator

[0377] QoS quality of service

[0378] RAN radio access network

[0379] Rel (e g., Rel- or Rel.) release

[0380] RT Round Trip

[0381] RTT round-trip time

[0382] Rx receiver

[0383] SDF Service Data Flow

[0384] SGW serving gateway

[0385] SMF session management function

[0386] TCP transmission control protocol

[0387] TNGF Trusted Non-3GPP Gateway Function

[0388] TRP transmission-reception point

[0389] TWIF Trusted WLAN Interworking Function

[0390] Tx transmitter

[0391] UDM unified data management

[0392] UDP User datagram protocol

[0393] UDR unified data repository

[0394] UE user equipment (e.g., a wireless, typically mobile device)

[0395] uplink uplink (from UE to network)

[0396] UP user plane

[0397] UPF user plane function

[0398] W-AGF Wireline Access Gateway Function

[0399] WLAN wireless local area network

[0400] XR extended reality

[0401] XRM Extended Reality and Media service

Claims

What is claimed is:

1. A method, comprising: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

2. The method according to claim 1, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

3. The method according to any of claims 1 or 2, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or more thresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

4. The method according to any of claims 1 to 3, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or adownlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session and one or more policy and charging control rules for the downlink multiple access protocol data unit session.

5. A method, comprising: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

6. The method according to claim 5, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

7. The method according to claim 5, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flowtemplate of one of the one or more policy and charging control rules and indicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

8. The method according to any of claims 5 to 7, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

9. The method according to any of claims 5 to 8, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific user equipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

10. The method according to any of claims 5 to 9, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

11. A method, comprising: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multiaccess protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; andbased on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

12. The method according to claim 11, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

13. The method according to claim 12, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

14. The method according to any of claims 11 to 13, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

15. The method according to claim 14, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

16. A method, comprising: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unitsession over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

17. The method according to claim 16, wherein the multiple accesses comprise a 3 GPP access and a non-3GPP access.

18. The method according to claim 17, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

19. The method according to any of claims 16 to 18, further comprising, prior to the receiving, sending from the user equipment to at least a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

20. The method according to any of claims 16 to 19, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

21. The method according to claim 20, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access,and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

22. A method, comprising: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multiaccess protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

23. The method according to claim 22, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along withcorresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

24. The method according to any of claims 22 to 23, further comprising sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprising one or more of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

25. The method according to any of claims 22 to 24, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a static quality of service parameter and the PSD is a quality of service parameter that is a real-time measured average value of PSDB that is a static quality of service parameter.

26. The method according to any of claims 22 to 25, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

27. The method according to any of claims 22 to 26, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

28. A method, comprising: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

29. The method according to claim 28, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unitbased flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

30. The method according to any of claims 28 to 29, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

31. The method according to claim 30, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

32. A method, comprising: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session;in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

33. The method according to claim 32, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

34. The method according to any of claims 32 to 33, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

35. The method according to claim 34, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

36. The method according to any of claims 1 to 35, wherein the data traffic comprises traffic for extended reality.

37. A computer program, comprising instructions for performing the methods of any of claims 1 to 36, when the computer program is run on an apparatus.

38. The computer program according to claim 37, wherein the computer program is a computer program product comprising a computer-readable medium bearing instructions embodied therein for use with the apparatus.

39. The computer program according to claim 37, wherein the computer program is directly loadable into an internal memory of the apparatus.

40. An apparatus, comprising means for performing: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising the parameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

41. The apparatus according to claim 40, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

42. The apparatus according to any of claims 40 or 41, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or more thresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

43. The apparatus according to any of claims 40 to 42, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or a downlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session and one or more policy and charging control rules for the downlink multiple access protocol data unit session.

44. An apparatus, comprising means for performing: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

45. The apparatus according to claim 44, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

46. The apparatus according to claim 44, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flow template of one of the one or more policy and charging control rules and indicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

47. The apparatus according to any of claims 44 to 46, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

48. The apparatus according to any of claims 44 to 47, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific user equipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

49. The apparatus according to any of claims 44 to 48, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

50. An apparatus, comprising means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session fordata traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multiaccess protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

51. The apparatus according to claim 50, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

52. The apparatus according to claim 51, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

53. The apparatus according to any of claims 50 to 52, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

54. The apparatus according to claim 53, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access,and the redistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

55. An apparatus, comprising means for performing: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unit session over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

56. The apparatus according to claim 55, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

57. The apparatus according to claim 56, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

58. The apparatus according to any of claims 55 to 57, wherein the means are further configured for performing, prior to the receiving, sending from the user equipment to atleast a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

59. The apparatus according to any of claims 55 to 58, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

60. The apparatus according to claim 59, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

61. An apparatus, comprising means for performing: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multiaccess protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should beused along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

62. The apparatus according to claim 61, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

63. The apparatus according to any of claims 61 to 62, wherein the means are further configured for performing sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprising one ormore of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

64. The apparatus according to any of claims 61 to 63, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a static quality of service parameter and the PSD is a quality of service parameter that is a realtime measured average value of PSDB that is a static quality of service parameter.

65. The apparatus according to any of claims 61 to 64, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

66. The apparatus according to any of claims 61 to 65, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

67. An apparatus, comprising means for performing: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session;in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

68. The apparatus according to claim 67, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

69. The apparatus according to any of claims 67 to 68, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

70. The apparatus according to claim 69, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

71. An apparatus, comprising means for performing: receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic fora multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

72. The apparatus according to claim 71, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and usingrules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

73. The apparatus according to any of claims 71 to 72, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

74. The apparatus according to claim 73, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

75. The apparatus according to any of claims 40 to 73, wherein the data traffic comprises traffic for extended reality.

76. The apparatus according to any preceding apparatus claim, wherein the means comprises: at least one processor; and at least one memory storing instructions that, when executed by at least one processor, cause the performance of the apparatus.

77. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a policy control function in a cellular network, a message for policy authorization for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, where the multi-access protocol data unit session uses sets of protocol data units and the message comprises parameters for quality of service for the sets of protocol data units; generating one or more policy and charging control rules comprising indication of one or more thresholds for traffic specific to protocol data unit sets; and sending, by the policy control function to a session management function in the cellular network, the one or more Policy and charging control rules comprising theparameters for quality of service for the sets of protocol data units and session control information for the multi-access protocol data unit session, the session control information comprising the indication of the one or more thresholds for the data traffic specific to the protocol data unit sets.

78. The apparatus according to claim 77, wherein the parameters for quality of service for the sets of protocol data units comprise one or more of thresholds for PSLR or PSD or both PSLR and PSD.

79. The apparatus according to any of claims 77 or 78, wherein the indication of the one or more thresholds comprise indication of one or more thresholds for PSLR or PSD or both PSLR and PSD for the data traffic and indication the one or more thresholds should be used when quality of service for protocol data unit sets is supported in a corresponding policy and charging control rule.

80. The apparatus according to any of claims 77 to 79, wherein the one or more policy and charging control rules are for an uplink multiple access protocol data unit session or a downlink multiple access protocol data unit session or there are one or more policy and charging control rules for the uplink multiple access protocol data unit session and one or more policy and charging control rules for the downlink multiple access protocol data unit session.

81. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, at a session management function in a cellular network, one or more policy and charging control rules for protocol data unit set specific data traffic comprising parameters for quality of service for the sets of protocol data units and session control information for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accessesbetween a user equipment and the cellular network, the session control information comprising indication of one or more thresholds for the traffic specific to protocol data unit sets; enabling, by the session management function, rules indicating how to split and steer the protocol data units of the protocol data unit set of the multi-access protocol data unit session over the multiple accesses to use at least the one or more thresholds for the traffic specific to protocol data unit sets, wherein individual ones of the enabled rules are enabled for uplink or downlink; and sending, by the session management function, one or more enabled rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more enabled rules for uplink to the user equipment for uplink data traffic for the multi-access protocol data unit session.

82. The apparatus according to claim 81, wherein the enabled rules comprise enabled rules indicating to use protocol data unit set loss rate and protocol data unit set delay that are measured to split and / or steer the protocol data units of the protocol data unit Set across the multiple accesses.

83. The apparatus according to claim 81, wherein a traffic descriptor for at least one of the enabled rules is generated by the session management function from a service data flow template of one of the one or more policy and charging control rules and indicates steering functionality is one of MPTCP, MPQUIC, or ATSSS-LL, and steering mode is one of load balancing, priority -based, or redundant, and the session management function sends indication of the steering functionality and the steering mode toward the user equipment and the user plane function.

84. The apparatus according to any of claims 81 to 83, wherein the one or more enabled rules for downlink sent to the user plane function are one or more modified N4 rules sent with an indication to activate protocol data unit set marking.

85. The apparatus according to any of claims 81 to 84, wherein the enabling rules and sending one or more enabled rules for uplink to a specific user equipment are performed in response to the session management function receiving from the specific user equipment an indication of capability to support the quality of service for the sets of protocol data units in uplink.

86. The apparatus according to any of claims 81 to 85, wherein the one or more enabled rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

87. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, one or more rules for downlink, the one or more rules for downlink data traffic for a multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating how to split and steer in downlink protocol data units of a protocol data unit set of the multiaccess protocol data unit session over multiple accesses and enabled to use at least one or more thresholds for protocol data unit set specific data traffic; performing, by the user plane function, performance measurements in at least downlink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for downlink and using the one or more thresholds for the performance measurements, redistributing by the user plane function downlink data traffic to the user equipment over the multiple accesses for the multi-access protocol data unit session.

88. The apparatus according to claim 87, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

89. The apparatus according to claim 88, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

90. The apparatus according to any of claims 87 to 89, wherein the redistributing downlink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

91. The apparatus according to claim 90, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access, and the redistributing downlink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

92. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user equipment connected to a cellular network and from a user plane function in the cellular network, one or more rules for uplink, the one or more rules for uplink enabled for uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between the user equipment and the cellular network, the one or more rules for uplink indicating how to split and steer protocol data units of a protocol data unit set of the multi-access protocol data unitsession over multiple accesses by using at least one or more thresholds for data traffic specific to the protocol data unit sets; performing, by the user equipment, performance measurements in at least uplink for quality of service for the sets of protocol data units in the data traffic specific to the protocol data unit sets of the multi-access protocol data unit session; and based on the one or more rules for uplink and using the one or more thresholds for the performance measurements, redistributing by the user equipment uplink data traffic from the user equipment to the cellular network over the multiple accesses for the multi-access protocol data unit session.

93. The apparatus according to claim 92, wherein the multiple accesses comprise a 3 GPP access and a non-3GPP access.

94. The apparatus according to claim 93, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

95. The apparatus according to any of claims 92 to 94, wherein the one or more memories further store instructions that, when executed by the one or more processors, cause the apparatus at least to perform, prior to the receiving, sending from the user equipment to at least a session management function an indication of capability to support quality of service for the sets of protocol data units in uplink.

96. The apparatus according to any of claims 92 to 95, wherein the redistributing uplink data traffic to the user equipment comprises one or more operations of steering, switching, or splitting between the multiple accesses and the operations take place at protocol data unit set boundaries for protocol data unit sets in the multi-access protocol data unit session.

97. The apparatus according to claim 96, wherein performing performance measurements comprises accessing performance measurements in order to estimate one or both of protocol data unit set Loss Rate (PSLR) or protocol data unit set Delay (PSD) that protocol data unit sets are expected to experience when transmitted on a certain access,and the redistributing uplink data traffic uses the one or more estimated PSLR or PSD in conjunction with the one or more thresholds.

98. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a session management function in a cellular network, a message comprising parameters for quality of service for sets of protocol data units for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, and comprising indication that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; modifying, by the session management function, rules indicating that if any one of available accesses does not support protocol data unit set handling for the multiaccess protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; and sending, by the session management function, one or more modified rules for downlink to a user plane function for downlink data traffic for the multi-access protocol data unit session and one or more modified rules for uplink to a user equipment for uplink data traffic for the multi-access protocol data unit session.

99. The apparatus according to claim 98, wherein the rules indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then a protocol data unit set based flow parameters for quality of service should be used along with corresponding rules indicate the following: if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then the protocol data unit based flow parameters for quality of service should be used to handle the protocol data units of the protocol data unit set and rules should be used corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and if all available accesses do support protocol data unit set handling for the multi-access protocol data unit session for the protocol data units of the protocol data unit set, then protocol data unit parameters for quality of service should be used to handle the protocol data unit sets and rules should be used corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

100. The apparatus according to any of claims 98 to 99, wherein the one or more memories further store instructions that, when executed by the one or more processors, cause the apparatus at least to perform sending, by the session management function to a non-3GPP access node, protocol data unit set parameters for quality of service comprising one or more of protocol data unit set specific delay (PSDB), protocol data unit set error rate (PSER), or protocol data unit set Importance (PSIHI) measurements.

101. The apparatus according to any of claims 98 to 100, wherein the PSLR is a quality of service parameter that is a real-time measured average value of PSER that is a staticquality of service parameter and the PSD is a quality of service parameter that is a realtime measured average value of PSDB that is a static quality of service parameter.

102. The apparatus according to any of claims 98 to 101, wherein the one or more modified rules for downlink sent to the user plane function are one or more modified N4 rules.

103. The apparatus according to any of claims 98 to 102, wherein the one or more modified rules for uplink sent to the user equipment are modified ATSSS rules sent in a NAS message.

104. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform: receiving, by a user plane function in a cellular network from a session management function in the cellular network, rules for downlink concerning downlink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the one or more rules for downlink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol dataunit session, using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules.

105. The apparatus according to claim 104, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for uplink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); and using by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for uplink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

106. The apparatus according to any of claims 104 to 105, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

107. The apparatus according to claim 106, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

108. An apparatus, comprising: one or more processors; and one or more memories storing instructions that, when executed by the one or more processors, cause the apparatus at least to perform:receiving, by a user equipment connected to cellular network and from a user plane function in the cellular network, rules for uplink concerning uplink data traffic for a multi-access protocol data unit session, the multi-access protocol data unit session for data traffic communicated over multiple accesses between a user equipment and the cellular network, the rules for uplink indicating that if any one of available accesses does not support protocol data unit set handling for the multi-access protocol data unit session for protocol data units of the protocol data unit sets, then protocol data unit based flow parameters for quality of service should be used along with corresponding rules, and if all the available accesses do support protocol data unit set handling, then protocol data unit set based flow parameters for quality of service should be used along with corresponding rules; determining, by the user plane function, whether any access of the multiple accesses does not support protocol data unit set handling for uplink for the multi-access protocol data unit session; in response to a determination that any access of the multiple accesses does not support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit based flow parameters for quality of service along with corresponding rules; and in response to a determination that all accesses of the multiple accesses support protocol data unit set handling for downlink for the multi-access protocol data unit session, using by the user equipment protocol data unit set based flow parameters for quality of service along with corresponding rules.

109. The apparatus according to claim 108, wherein: using by the user plane function protocol data unit based flow parameters for quality of service along with corresponding rules comprises using the protocol data unit based flow parameters for quality of service to handle the protocol data units of the protocol data unit set and using rules for downlink corresponding to parameters for quality of service comprising one or more of protocol data unit session specific Packet Delay Budget (PDB) or Packet Error Rate (PER); andusing by the user plane function protocol data unit set based flow parameters for quality of service along with corresponding rules comprises using protocol data unit parameters for quality of service to handle the protocol data unit sets and using rules for downlink corresponding to parameters for quality of service comprising PSLR or PSD or both PSLR and PSD.

110. The apparatus according to any of claims 108 to 109, wherein the multiple accesses comprise a 3GPP access and a non-3GPP access.

111. The apparatus according to claim 110, wherein the non-3GPP access comprises access over one of N3IWF, TNGF, W-AGF.

112. The apparatus according to any of claims 77 to 111, wherein the data traffic comprises traffic for extended reality.

Images