Network and method for processing conflict between PDU session modification process requested by UE and PDU session modification process requested by network

Abstract

A network and a method of handling a conflict between a PDU session modification procedure requested by a UE and a PDU session modification procedure requested by the network are provided. When a conflict occurs and a connection capability is included in a PDU SESSION MODIFICATION REQUEST message received from user equipment (UE), a network determines that the UE has the capability of supporting the execution of a URSP rule according to the connection capability included in the PDU SESSION MODIFICATION REQUEST message, and a PDU session modification process requested by the UE and started by the PDU SESSION MODIFICATION REQUEST message will not continue to be carried out.

Description

[0001] Cross-referencing

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 503,178, filed May 19, 2023, the contents of which are incorporated herein by reference. [Technical Field]

[0003] The disclosed embodiments generally relate to wireless communication, and more specifically, to a network and method for handling a conflict between a Protocol Data Unit (PDU) session modification process requested by a UE and a PDU session modification process requested by a network. [Background Technology]

[0004] The background description provided herein is intended to present the general context of this disclosure. The work of the currently named inventor, within the scope of the work described in this background section, and in respect of descriptions that may not qualify as prior art at the time of filing, is not expressly or implicitly challenged as prior art to this disclosure.

[0005] In the field of fifth-generation wireless systems (5G), Protocol Data Unit (PDU) sessions play a crucial role in enabling seamless data transmission between user equipment and networks (such as the Internet). These PDU sessions act as dedicated paths, ensuring the efficient and reliable delivery of application data packets.

[0006] In 5G, the PDU session modification process enables User Equipment (UE) and the network to modify parameters of existing PDU sessions. However, a situation may arise where the UE and the network simultaneously initiate PDU session modification requests for the same PDU session. This situation is known as a conflict between the UE-requested PDU session modification process and the network-requested PDU session modification process. In 5G PDU session modification conflict scenarios, conflicts are resolved by prioritizing requests and applying the priority modification. Non-priority requests are rejected or aborted based on their origin (UE or network). This structured approach ensures that UE and network modifications are processed efficiently and in a controlled manner.

[0007] In the context of 5G networks defined by 3GPP specifications, UE Routing Policy (URSP) plays a crucial role in achieving efficient and flexible traffic management. URSP is a mechanism that allows the network to dynamically allocate traffic from user equipment (UE) to appropriate network slices based on specific criteria. This dynamic routing capability is essential for supporting diverse network slicing scenarios and ensuring optimal resource utilization in 5G networks. [Summary of the Invention]

[0008] In one embodiment of this disclosure, a method is disclosed for handling a conflict between a Protocol Data Unit (PDU) session modification process requested by a UE and a PDU session modification process requested by a network. The method includes: when a network receives a PDU SESSION MODIFICATION REQUEST message from a user equipment (UE) during a network-requested PDU session modification process, the network determines whether a PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches a PDU session associated with the network-requested PDU session modification process; if the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches a PDU session associated with the network-requested PDU session modification process, the network determines that a conflict has occurred and determines whether the PDU SESSION MODIFICATION REQUEST message contains a connectivity capability; and if the conflict has occurred and the PDU SESSION MODIFICATION REQUEST message contains the connectivity capability, the network ignores the portion of the PDU SESSION MODIFICATION REQUEST message other than the connectivity capability and continues the network-requested PDU session modification process.

[0009] In another embodiment of this disclosure, a method for handling conflicts between a network and a user equipment (UE) is disclosed. The method includes: during a network-requested PDU session modification process, when the network receives a request message from a UE requesting a Protocol Data Unit (PDU) session modification process, the network determines whether a PDU session indicated in the request message matches a PDU session associated with the network-requested PDU session modification process; if the PDU session indicated in the request message matches a PDU session associated with the network-requested PDU session modification process, the network determines that a conflict has occurred and determines whether the request message contains a connectivity capability; and if a conflict has occurred and the request message contains the connectivity capability, the network ignores the portion of the request message other than the connectivity capability and continues the network-requested PDU session modification process.

[0010] In another embodiment of this disclosure, a network is disclosed. The network includes a Session Management Function (SMF), an Access and Mobility Management Function (AMF), a User Plane Function (UPF), and a Policy Control Function (PCF). The SMF is configured to exchange signaling messages with a User Equipment (UE). The AMF is configured to forward session management-related signaling messages between the SMF and the UE. The UPF is configured to perform the establishment, modification, and release of a Protocol Data Unit (PDU) session between the network and the UE. The PCF is configured to propagate a UE Routing Policy (URSP) to the UE and the AMF. When the network receives a PDU SESSION MODIFICATION REQUEST message from the UE requesting a PDU session modification procedure, the SMF determines whether the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the network-requested PDU session modification procedure. If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the network-requested PDU session modification process, the SMF determines that a conflict has occurred and determines whether the PDU SESSION MODIFICATION REQUEST message includes a connectivity capability. If the conflict occurs and the PDU SESSION MODIFICATION REQUEST message includes the connectivity capability, the SMF ignores the portion of the PDU SESSION MODIFICATION REQUEST message other than the connectivity capability and continues with the network-requested PDU session modification process.

[0011] These, and other objectives of the invention, will undoubtedly become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments, as well as the various figures and illustrations. [Attached Image Description]

[0012] Figure 1 A communication system according to an embodiment of the present disclosure is shown.

[0013] Figure 2 An example of a PDU session according to an embodiment of this disclosure is shown.

[0014] Figure 3 This shows an example of a UE requesting the establishment of a PDU session.

[0015] Figure 4This demonstrates an example procedure for a communication system to handle a PDU session modification process initiated by the network's Session Management Function (SMF).

[0016] Figure 5 This demonstrates an example procedure for a communication system to handle a PDU session modification procedure initiated by the UE and requested by the UE.

[0017] Figure 6 This shows an example of a conflict between a UE and the network's Session Management Function (SMF).

[0018] Figure 7 This demonstrates a conflict between a PDU session modification process that handles a UE request and a PDU session modification process that handles a network request.

Detailed Implementation Methods

[0019] Figure 1 A communication system 100 according to an embodiment of this disclosure is shown. The communication system 100 may be a fifth-generation system (5GS) including a user equipment (UE) 110, an access network (AN) 120, a network 130, and a data network (DN) 140. The network 130 may be a fifth-generation core (5GC) network and may support various network functions, including access and mobility management functions (AMF) 131, session management functions (SMF) 132, user plane functions (UPF) 133, and policy control functions (PCF) 134. Each network function may be implemented as a network element on dedicated hardware, or as a software instance running on dedicated hardware, or as a virtualized function instantiated on a suitable platform (e.g., cloud infrastructure). AMF 131, SMF 132, UPF 133 and PCF 134 are coupled to each other and can coordinate with each other to establish, modify or release Protocol Data Unit (PDU) sessions 101 between UE 110 and DN 140 to exchange data units (e.g., IP packets, Ethernet frames, unstructured data, etc.).

[0020] UE 110 can be a mobile phone, laptop, vehicle, etc. AN 120 can be a 3GPP wireless network (e.g., a gNB as defined in the 3GPP New Radio Standard), or a non-3GPP network (e.g., Wi-Fi, WiMAX, or a fixed network). UE 110 includes a transceiver 111 and a processor 112. Transceiver 111 may include one or more antennas for wirelessly receiving signals from network 130 and transmitting signals to network 130. Processor 112 is coupled to transceiver 111 for processing the signals received by transceiver 111. Processor 112 invokes different functional modules and circuits to perform functions in UE 110. Network 130 is defined in the 3GPP 5G standard. AMF 131 can be configured to forward session management-related signaling messages between SMF 132 and UE 110. SMF 132 is configured to exchange signaling messages with UE 110, AN 120, and UPF 133 to perform session management functions, such as the establishment, modification, and release of PDU session 101. PCF 134 acts as a policy enforcer, applying policies and rules to control network behavior. PCF 134 can propagate UE routing policies (URSPs) to UE 110 and AMF 131.

[0021] If UE 110 has the capability to support URSP rule enforcement, PCF 134 can instruct UE 110 to send a report on URSP rule enforcement. If PCF 134 instructs UE 110 to send a report on URSP rule enforcement, and if the UE URSP rules include connectivity capabilities in the Traffic Descriptor (TD), when UE 110 associates newly detected applications with an existing PDU session based on URSP evaluation results, UE 110 should send a PDUSESSION MODIFICATION REQUEST message containing the connectivity capabilities contained in the TD of the associated URSP rules. Connectivity capabilities are defined in the UE Routing Policy (URSP) rule enforcement and may include QoS parameters (e.g., data rate, latency, and packet loss rate), security information (e.g., encryption algorithms and authentication methods), and additional information (e.g., network load, congestion level, and service availability).

[0022] In operation, the 5GSM session management procedure can be performed via a Non-Access Stratum (NAS) signaling connection between UE 110 and AMF 131 to handle PDU connections in UE 110 and SMF 132. For example, the 5GMM protocol can operate between UE 110 and AMF 131 and be used as a transport protocol. 5GSM messages of the 5GSM protocol can be piggybacked in 5GMM transport messages. For example, 5GSM messages can be transmitted in the Information Elements (IEs) of 5GMM transport messages. The 5GSM procedure may include a UE-requested PDU session establishment procedure, a PDU session modification procedure, and a PDU session release procedure.

[0023] Figure 2 An example of a PDU session 101 according to an embodiment of this disclosure is shown. PDU session 101 may be an IPv4, IPv6, IPv4v6, Ethernet, or similar PDU session type. PDU session 101 may include one or more Quality of Service (QoS) flows 210 to 220. Each QoS flow 210 to 220 has a QoS flow identifier (QFI) and is associated with one or more QoS rules, and may further be associated with a QoS flow description. For example, QoS flow 210 with QFI = 1 is associated with QoS rules 211 to 212, and may further be associated with a QoS flow description 219. QoS flow 220 with QFI = 2 is associated with QoS rules 221 to 222, and may further be associated with a QoS flow description 229. QoS rules 211 to 212 and 221 to 222, as well as QoS flow descriptions 219 to 229, are crucial because they determine how different types of data in communication system 100 are processed, ensuring that each packet receives an appropriate level of service.

[0024] The QoS rules for PDU session 101 can be derived from network 130 signaling when PDU session 101 is established or modified, or locally using a reflection QoS scheme. The QoS rules for each signaling session, such as QoS rules 211 to 212 and 221 to 222, can include multiple components. These components include an indication of whether the QoS rule is the default QoS rule, a QoS rule identifier (QRI), and a QoS flow identifier (QFI) corresponding to the associated QoS flow. Additionally, the QoS rules for each signaling session may also include a set of packet filters (packet filter set) and priority values. The packet filter set may include zero or more packet filters for uplink or downlink (besides matching all packet filters). These packet filters are used to classify data units into the appropriate QoS flow. The default QoS rule may include matching all packet filters and is typically assigned the lowest priority. During filtering operations, the filter set is used according to the priority of the corresponding QoS rule. Packets that do not match other packet filters can be collected into the QoS flow associated with the default QoS rule, referred to as the default QoS flow.

[0025] Figure 3 This shows an example of a UE-requested PDU session establishment process 300. The UE-requested PDU session establishment process 300 may include steps S310 to S320 and is performed between UE 110 and SMF 132 to establish a target PDU session.

[0026] In step S310, 311 can be transmitted from UE 110 to SMF 132. The PDU SESSION ESTABLISHMENTREQUEST message 311 may include an associated PDU session ID, a PDU session type information element (IE), a session and service continuity (SSC) mode IE, the maximum number of packet filters supported by UE 110, a requested data network name (DNN), etc.

[0027] In step S320, the PDU SESSION ESTABLISHMENT ACCEPT message 321 can be transmitted from SMF 132 to UE 110. The PDU SESSION ESTABLISHMENT ACCEPT message 321 may include an authorized QoS rule IE that is set to authorize the QoS rule for the target PDU session.

[0028] In 5G, the PDU session modification process is a crucial one, allowing the network to adapt to changing conditions and demands. By dynamically adjusting QoS rules 211 to 212 and 221 to 222, as well as QoS flow descriptions 219 to 229, the communication system 100 can prioritize critical data, optimize resource allocation, and maintain overall network performance. This means that the most important data can be transmitted first, resources can be allocated where they are most needed, and the network can continue to operate optimally even under changing conditions. By prioritizing critical data, optimizing resource allocation, and adapting to dynamic demands, the PDU session enables 5G networks to deliver the seamless connectivity and high-performance experience that users crave. The PDU session modification process can be requested by SMF 132 or UE 110.

[0029] Figure 4 An example process 400 of communication system 100 is shown for processing a PDU session modification process initiated by SMF 132 of network 130. Process 400 may include steps S410 to S420 (or S430) and is performed by SMF 132 and UE 110 to modify an existing PDU session.

[0030] In step S410, SMF 132 of network 130 sends 411 to UE 110 to initiate a network-requested PDU session modification procedure. If the network-requested PDU session modification procedure is accepted by UE 110, then step S420 is executed; otherwise, step S430 is executed.

[0031] In step S420, UE 110 may transmit a PDU SESSION MODIFICATION COMPLETE message 421 to SMF 132. Alternatively, in step S430, UE 110 may transmit a PDU SESSION MODIFICATION COMMANDREJECT message 431, which includes a 5GSM reason IE indicating the reason for rejecting PDU session modification. For example, the 5GSM reason IE may include values ​​such as #26, insufficient resources; #43, invalid PDU session identifier; #44, semantic error in packet filter; #45, syntax error in packet filter; #83, semantic error in QoS operation; #84, syntax error in QoS operation; or similar.

[0032] Figure 5 An example procedure 500 of the communication system 100 is shown for processing a PDU session modification procedure requested by a UE initiated by a UE 110. Procedure 500 may include steps S510 to S520 (or S530) and is executed by the SMF 132 and the UE 110 to modify an existing PDU session.

[0033] In step S510, UE 110 sends a PDU SESSION MODIFICATION REQUEST message 511 to SMF 132 to initiate the UE-requested PDU session modification procedure. If the UE-requested PDU session modification procedure is accepted by SMF 132 of network 130, then step S520 is executed; otherwise, step S530 is executed.

[0034] In step S520, SMF 132 continues the PDU session modification process for the network request triggered by the accepted UE request, and transmits a PDU SESSION MODIFICATION ACCEPT message to UE 110. In step S530, SMF 132 may transmit a PDU SESSION MODIFICATION REJECT message 531, which includes a 5GSM reason IE indicating the reason for rejecting the PDU session modification. For example, the 5GSM reason IE may include the value #43, an invalid PDU session identifier; #95, a protocol error or semantically incorrect message; or similar situations.

[0035] Figure 6 This illustrates an example conflict between UE 110 and SMF 132 of network 130. A conflict occurs when SMF 132 sends a PDU SESSION MODIFICATION COMMAND message 411 to UE 110 to initiate a network-requested PDU session modification procedure, and UE 110 sends a PDU SESSION MODIFICATION REQUEST message 511 to SMF 132 to initiate a UE-requested PDU session modification procedure, and the PDU session indicated in PDU SESSION MODIFICATION REQUEST message 511 matches the PDU session associated with the network-requested PDU session modification procedure. In this case, SMF 132 receives PDU SESSION MODIFICATION REQUEST message 511 from UE 110 during the network-requested PDU session modification procedure. In other words, SMF 132 receives PDU SESSION MODIFICATION REQUEST message 511 in the PDU SESSION MODIFICATION PENDING state, which is a state defined in the 3GPP specification.

[0036] Figure 7The process 700 illustrates the conflict between the UE-requested PDU session modification process and the network-requested PDU session modification process. When the network 130 receives a PDU SESSION MODIFICATION REQUEST message 511 from the UE 110 during the network-requested PDU session modification process, the SMF 132 determines whether a conflict has occurred between the UE-requested PDU session modification process and the network-requested PDU session modification process by determining whether the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message 511 matches the PDU session associated with the network-requested PDU session modification process. If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message is different from the PDU session associated with the network-requested PDU session modification process, the SMF 132 determines that no conflict has occurred, and then the SMF 132 continues with both the UE-requested PDU session modification process and the network-requested PDU session modification process. If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message 511 matches the PDU session associated with the network-requested PDU session modification procedure, SMF 132 determines that a conflict has occurred. When SMF 132 determines that a conflict has occurred, SMF 132 further determines whether the PDU SESSION MODIFICATION REQUEST message 511 includes connectivity capabilities defined in the UE Routing Policy (URSP) rule enforcement.

[0037] After SMF 132 determines whether the PDU SESSION MODIFICATION REQUEST message 511 includes connectivity capabilities, process 700 can proceed subsequently. Different groups of steps may be performed in process 700 depending on the scenario (e.g., scenarios 750A and 750B).

[0038] In the first scenario of 750A, if a conflict is determined to have occurred and the PDU SESSION MODIFICATION REQUEST message 511 includes connectivity capabilities, step S710 can be executed. In step S710, the session management function (SMF) 132 ignores the portion of the PDU SESSION MODIFICATION REQUEST message 511 other than connectivity capabilities and continues the PDU session modification process requested by the network. Therefore, the SMF 132 can determine that the user equipment (UE) 110 has the capability to support the execution of UE Route Selection Policy (URSP) rules based on the connectivity capabilities contained in the PDU SESSION MODIFICATION REQUEST message 511, without continuing the PDU session modification process requested by the UE.

[0039] In the second scenario of 750B, if a conflict is determined to have occurred and the PDU SESSION MODIFICATION REQUEST message 511 does not include connectivity capabilities, step S720 can be executed. In step S720, the SMF 132 ignores the entire PDU SESSION MODIFICATION REQUEST message 511 and continues the PDU session modification process requested by the network. Therefore, the PDU session modification process requested by the UE will not continue.

[0040] When SMF 132 ignores PDU SESSION MODIFICATION REQUEST message 511, it means that SMF 132 will not send PDU SESSION MODIFICATION REJECT message 531 and / or PDU SESSION MODIFICATION COMMAND message 411 to UE 110.

[0041] In summary, this disclosure provides a network and a method for handling conflicts between a UE-requested PDU session modification process and a network-requested PDU session modification process. When a conflict occurs and the PDU SESSION MODIFICATION REQUEST message includes connectivity capabilities, the network can determine that the UE has the capability to support URSP rule execution based on the connectivity capabilities contained in the PDU SESSION MODIFICATION REQUEST message, and the UE-requested PDU session modification process will not continue.

[0042] Those skilled in the art will readily observe that numerous modifications and alterations can be made to the apparatus and method while retaining the edible content of the present invention. Therefore, the above disclosure should be interpreted only within the scope and limits of the appended claims.

Claims

1. A method for handling a conflict between a Protocol Data Unit (PDU) session modification procedure requested by a UE and a PDU session modification procedure requested by a network, comprising: When a network receives a PDU SESSION MODIFICATION REQUEST message from a user equipment (UE) during a network-requested PDU session modification process, the network determines whether a PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the network-requested PDU session modification process. If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the PDU session modification procedure requested by the network, the network determines that a conflict has occurred and determines whether the PDU SESSION MODIFICATION REQUEST message contains a connectivity capability. as well as If the conflict has occurred and the PDU SESSION MODIFICATION REQUEST message contains the connectivity capability, the network ignores the portion of the PDU SESSION MODIFICATION REQUEST message other than the connectivity capability and continues the PDU session modification process requested by the network.

2. The method of claim 1, further comprising: If the conflict has occurred and the PDU SESSION MODIFICATION REQUEST message does not contain the connectivity capability, the network ignores the PDU SESSION MODIFICATION REQUEST message and continues the PDU session modification process requested by the network.

3. The method of claim 1, further comprising: If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message is different from the PDU session associated with the PDU session modification procedure requested by the network, the network continues with both the PDU session modification procedure requested by the UE and the PDU session modification procedure requested by the network.

4. The method of claim 1, further comprising: The network sends a PDU SESSION MODIFICATION COMMAND message to the UE to initiate the PDU session modification process requested by the network.

5. The method of claim 1, wherein the UE initiates the UE-requested PDU session modification process by sending the PDU SESSIONMODIFICATION REQUEST message to the network.

6. The method of claim 1, wherein the connectivity capability is defined in the execution of UE routing policy (URSP) rules.

7. The method of claim 1, wherein the network is a fifth-generation core (5GC) network.

8. A method for handling conflicts between a network and a user equipment (UE), comprising: During a network-requested PDU session modification process, when the network receives a request message from a UE requesting a Protocol Data Unit (PDU) session modification process, the network determines whether a PDU session indicated in the request message matches a PDU session associated with the network-requested PDU session modification process. If the PDU session indicated in the request message matches the PDU session associated with the PDU session modification procedure requested by the network, the network determines that a conflict has occurred and determines whether the request message contains a connectivity capability. If the conflict has occurred and the request message contains the connectivity capability, the network ignores the part of the request message other than the connectivity capability and continues the PDU session modification process requested by the network.

9. The method of claim 8, further comprising: If the conflict has occurred and the request message does not contain the connectivity capability, the network ignores the request message and continues the PDU session modification process requested by the network.

10. The method of claim 8, further comprising: If the PDU session indicated in the request message is different from the PDU session associated with the PDU session modification procedure requested by the network, the network continues with both the PDU session modification procedure requested by the UE and the PDU session modification procedure requested by the network.

11. The method of claim 8, further comprising: The network sends a command message to the UE to initiate the PDU session modification process requested by the network.

12. The method of claim 8, wherein the UE initiates a PDU session modification process requested by the UE by sending the request message to the network.

13. The method of claim 8, wherein the connectivity capability is defined in the execution of UE routing policy (URSP) rules.

14. The method of claim 8, wherein the network is a fifth-generation core (5GC) network.

15. A network comprising: A Session Management Function (SMF) is configured to exchange signaling messages with a User Equipment (UE). An Access and Mobility Management Function (AMF) is configured to forward session management-related signaling messages between the SMF and the UE; A User Plane Function (UPF) is configured to perform the establishment, modification, and release of a Protocol Data Unit (PDU) session between the network and the UE; A policy control function (PCF) is configured to propagate a UE routing policy (URSP) to the UE and the AMF; In the process of a network requesting a PDU session modification, when the network receives a PDU SESSION MODIFICATION REQUEST message from the UE requesting a PDU session modification process, the SMF determines whether the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the network requesting the PDU session modification process. If the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message matches the PDU session associated with the PDU session modification procedure requested by the network, the SMF determines that a conflict has occurred and determines whether the PDU SESSION MODIFICATION REQUEST message includes a connectivity capability. If the conflict occurs and the PDU SESSION MODIFICATION REQUEST message includes the connectivity capability, the SMF ignores the part of the PDU SESSION MODIFICATION REQUEST message other than the connectivity capability and continues the PDU session modification process for the network request.

16. The network of claim 15, wherein if the conflict occurs and the PDU SESSION MODIFICATION REQUEST message does not include the connectivity capability, the SMF ignores the PDU SESSION MODIFICATION REQUEST message and continues the PDU session modification process for the network request.

17. The network of claim 15, wherein if the PDU session indicated in the PDU SESSION MODIFICATION REQUEST message is different from the PDU session associated with the network-requested PDU session modification process, the SMF continues the UE-requested PDU session modification process and the network-requested PDU session modification process.

18. The network of claim 15, wherein the network sends a PDU SESSION MODIFICATIONCOMMAND message to the UE to initiate a PDU session modification procedure requested by the network.

19. The network of claim 15, wherein the UE initiates the UE-requested PDU session modification process by sending the PDU SESSIONMODIFICATION REQUEST message to the network.

20. The network of claim 15, wherein the connectivity capability is defined in the execution of the UE routing policy (URSP) rule.

Images