Method for implementing flexible data distribution under multiple accesses

Abstract

The application discloses a method for realizing flexible data distribution under multi-access, and relates to the technical field of data distribution, and comprises the following steps: when a MAPDU session is established and a policy is issued, an ATSSS rule is issued to a UE, and an N4 rule is sent to a UPF, wherein the rule introduces a composite distribution mode comprising three modes of priority-based distribution, load balancing and redundancy; when the composite distribution mode is selected, a threshold value of RTT or PLR is set, and the UE and the UPF respectively calculate the RTT or PLR of 3GPP and non-3GPP access channels through PMF; under the composite distribution mode, load balancing or priority-based distribution is used as a default distribution mode before the RTT or PLR reaches a switching condition, after the RTT or PLR reaches the switching condition, a PMF distribution mode switching report message is used to inform a peer end that the distribution mode is switched from the default mode to the redundancy mode, and the PMF distribution mode recovery report message is used to inform the return to the default mode before the RTT or PLR recovers to the switching condition. The application can switch the distribution mode without a special process for issuing a newly generated rule.

Description

Technical Field

[0001] This invention relates to the field of data offloading technology, specifically a method for flexible data offloading under multiple access conditions. Background Technology

[0002] For multi-access scenarios such as 5G+WiFi convergence, 3GPP has defined the ATSSS feature, which enables network selection, seamless migration and segmentation of traffic between two access systems by establishing multi-access PDU sessions. Currently, it supports primary / backup, minimum latency, priority-based, and load-balanced traffic splitting modes. In primary / backup mode, the primary access is used when available, and switched to the backup access when unavailable. Minimum latency mode switches to the access with the minimum RTT (Round-Trip Time) based on measurement results. Priority-based mode directs all traffic to high-priority access until congestion occurs, then uses low-priority access. Load-balanced mode allows specifying the percentage of traffic sent by 3GPP and non-3GPP access. In addition to a fixed split ratio, it enhances UE-assisted operation, supporting the UE to send auxiliary instructions based on current battery consumption and other factors to apply different split percentages to uplink traffic. It also supports the UE and UPF to autonomously decide on uplink and downlink traffic splitting by providing autonomous load-balanced instructions. Furthermore, for priority-based and load-balanced traffic splitting modes, it can combine RTT and / or PLR (Packet Loss Ratio) threshold conditions to stop or reduce the data flow transmitted on a certain access channel when the threshold is exceeded. The current Rel-18 version also introduces a new redundant offloading mode to enhance the reliability of data transmission. This offloading mode can operate with or without RTT and PLR thresholds.

[0003] While existing ATSSS technology supports multiple traffic splitting modes, it can only support one of them for a specific service flow. When network conditions change and the traffic splitting mode needs to be changed, such as from load balancing mode to redundant transmission mode, the network side needs to measure and calculate relevant performance parameters, and then the PCF (with dynamic PCC deployed) or SMF (without dynamic PCC deployed) locally regenerates ATSSS rules and N4 rules and initiates a multi-access PDU session update process to send them to the UE and UPF respectively. This has the problems of complex process and slow adaptation. Summary of the Invention

[0004] This invention addresses the needs and shortcomings of current technological development by providing a method for flexible data distribution under multiple access conditions.

[0005] The present invention provides a method for flexible data splitting under multiple access conditions, and the technical solution adopted to solve the above-mentioned technical problems is as follows:

[0006] A method for flexible data splitting under multiple access conditions, the implementation of which includes:

[0007] When establishing the MA PDU session delivery policy, ATSSS rules are sent to the UE and N4 rules are sent to the UPF. The ATSSS and N4 rules include six traffic offloading modes: primary / backup, minimum delay, priority-based, load balancing, redundancy, and composite. The composite traffic offloading mode includes three types: priority-based, load balancing, and redundancy. When the traffic offloading mode is the composite traffic offloading mode, the threshold value of round-trip time (RTT) or packet loss rate (PLR) is set. The UE and UPF respectively calculate the round-trip time (RTT) or packet loss rate (PLR) of the 3GPP and non-3GPP access channels through the PMF.

[0008] In the composite traffic splitting mode, before the round-trip time (RTT) or packet loss rate (PLR) reaches the switching condition, load balancing or priority-based traffic splitting mode is used as the default traffic splitting mode. After the RTT or PLR reaches the switching condition, a PMF traffic splitting mode switching report message is used to notify the peer that the traffic splitting mode has switched from the default traffic splitting mode to the redundant traffic splitting mode. When the RTT or PLR recovers to the level before the switching condition, a PMF traffic splitting mode recovery report message is used to notify the peer to return to the default traffic splitting mode.

[0009] Optionally, in the composite load balancing mode, if no default load balancing mode is specified, the default load balancing mode with a fixed split ratio of 50% is used.

[0010] Optionally, in the composite traffic splitting mode, when load balancing is used as the default traffic splitting mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of at least one access channel in the 3GPP and non-3GPP access channels reaches the set threshold value.

[0011] Further optional, in the composite traffic splitting mode, load balancing is used as the default traffic splitting mode before the round-trip time (RTT) of the 3GPP and non-3GPP access channels or the packet loss rate (PLR) in the uplink and downlink directions reaches the switching conditions.

[0012] When the UE calculates that the round-trip time (RTT) or uplink packet loss rate (PLR) of at least one access channel meets the handover conditions, it sends a PMF traffic splitting mode handover report to the UPF to notify that the uplink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UE copies the data packets, the UPF deduplicates the subsequent received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UPF to reuse the default load balancing mode.

[0013] When the UPF calculates that the round-trip time (RTT) or downlink packet loss rate (PLR) of at least one access channel meets the handover conditions, it sends a PMF traffic splitting mode handover report to the UE to notify that the downlink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UPF copies the data packets, the UE performs deduplication on the subsequent received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UE to reuse the default load balancing mode.

[0014] Optionally, in the composite traffic offloading mode, when priority-based traffic offloading is used as the default offloading mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of the high-priority access channel in the 3GPP and non-3GPP access channels reaches the set threshold value.

[0015] Further optional, in the composite traffic splitting mode, before the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of the 3GPP and non-3GPP access channels reaches the handover condition, priority-based traffic splitting mode is adopted as the default.

[0016] After the UE or UPF calculates that the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of at least one access channel meets the handover conditions, if the high-priority access channel meets the handover conditions, a PMF traffic splitting mode handover report notification is sent to switch the priority-based default mode to the redundancy mode. If the low-priority access channel meets the handover conditions, no PMF traffic splitting mode handover report is sent, the priority-based default mode is maintained, and only the high-priority access channel is used.

[0017] Further optionally, in the composite traffic splitting mode, when the UE receives the PMF traffic splitting mode switching report message sent by the UPF, it changes the traffic splitting mode in the downlink direction or changes the traffic splitting mode in the bidirectional link.

[0018] Alternatively, in the composite traffic splitting mode, when the UPF receives a PMF traffic splitting mode switching report message sent by the UE, it changes the traffic splitting mode in the uplink direction or changes the traffic splitting mode in the bidirectional link.

[0019] The method for flexible data splitting under multiple access conditions proposed in this invention has the following advantages compared with the prior art:

[0020] This invention introduces a composite traffic splitting mode into the ATSSS rules sent to the UE and the N4 rules sent to the UPF, and sets threshold values ​​for round-trip time (RTT) or packet loss rate (PLR). When network conditions are good, the load balancing or priority-based default traffic splitting mode in the composite traffic splitting is used. When network conditions are poor, the existing PMF message notification is extended to directly switch to the redundant traffic splitting mode. There is no need to generate new rules and use a dedicated process for distribution. It has the characteristics of traffic aggregation and link backup, and achieves a balance between bandwidth and reliability. Attached Figure Description

[0021] Appendix Figure 1 This is a schematic diagram of the method flow of Embodiment 1 of the present invention;

[0022] Appendix Figure 2 This is a schematic diagram illustrating the switching of the load balancing mode in the composite load balancing mode of this invention. Detailed Implementation

[0023] To make the technical solution, the technical problem solved, and the technical effect of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments.

[0024] The following examples involve the explanation of the relevant English words:

[0025] 3GPP stands for 3rd Generation Partnership Project.

[0026] ATSSS stands for Access Traffic Steering, Switching and Splitting.

[0027] UE, User Terminal.

[0028] UPF stands for User Plane Function.

[0029] PCF stands for Policy Control Function.

[0030] PCC stands for Policy and Charging Control.

[0031] SMF stands for Session Management Function.

[0032] PDU, short for Protocol Data Unit, is a unit of information exchanged between peer layers in a protocol layer. A PDU session refers to the communication process between a user terminal (UE) and a data network (DN). Once a PDU session is established, a data transmission channel between the UE and the DN is established.

[0033] RTT stands for Round-Trip Time.

[0034] PLR stands for Packet Loss Ratio.

[0035] PMF stands for Performance Measurement Functionality.

[0036] Example 1:

[0037] Combined with appendix Figure 1 This embodiment proposes a method for flexible data splitting under multiple access conditions, the implementation of which includes:

[0038] (i) When establishing the MA PDU session distribution policy, ATSSS rules are sent to the UE and N4 rules are sent to the UPF. The ATSSS and N4 rules contain six traffic distribution modes: primary / backup, minimum delay, priority-based, load balancing, redundancy, and composite. The composite traffic distribution mode includes three types: priority-based, load balancing, and redundancy.

[0039] The structure of ATSSS rules is as follows:

[0040]

[0041]

[0042] When using a composite traffic splitting mode, threshold values ​​are mandatory and must include either the maximum RTT or the maximum PLR value (one of the two). A default mode can also be set to indicate the default traffic splitting mode when the RTT or PLR does not meet the switching conditions. If no default mode is specified, a 50% fixed split ratio load balancing mode is used by default. When the RTT or PLR value of at least one access (3GPP or non-3GPP) meets the switching conditions—for example, for the default load balancing mode, the switching condition is that the RTT or PLR value of at least one access channel exceeds the threshold—it indicates that the network condition of that link is poor. In this case, there is no need for a multi-access session update process; an extended PMF message can be used to notify the change in traffic splitting mode, converting the traffic splitting mode to redundant traffic splitting to improve data transmission reliability. For the priority-based default mode, if the high-priority access channel exceeds the threshold, the traffic splitting mode is also converted to redundant traffic splitting. However, if the low-priority access channel exceeds the threshold, no message is sent, and the original priority-based traffic splitting mode is maintained, still using only the high-priority access channel.

[0043] It should be noted that, since only fixed-weight load balancing and priority-based load balancing modes currently support threshold values ​​(RTT, packet loss rate), and the application of composite mode requires the combination of threshold values, the default value of composite mode is set to "load balancing" or "priority-based".

[0044] Similar to the ATSSS rules sent to the UE, the MAR in the N4 rules sent to the UPF introduces "composite" traffic splitting mode, and sets the threshold value for maximum RTT or maximum PLR. The default mode value is load balancing or priority-based. If not provided, the default mode uses load balancing with a fixed split ratio of 50% or 50%.

[0045] The MAR attribute in the N4 rule is as follows:

[0046]

[0047]

[0048] (ii) When the traffic splitting mode is the composite traffic splitting mode, set the threshold value of round-trip time (RTT) or packet loss rate (PLR). The UE and UPF respectively calculate the round-trip time (RTT) or packet loss rate (PLR) of the 3GPP and non-3GPP access channels through the PMF.

[0049] In existing technologies, the UE and UPF calculate the round-trip time (RTT) and packet loss rate (PLR) by exchanging PMF messages, such as using PMF-Echo Request and PMF-Echo Response to calculate RTT and exchanging PMF-PLR Report messages to calculate PLR.

[0050] (III) Under the composite diversion mode

[0051] Before the round-trip time (RTT) or packet loss rate (PLR) reaches the switching condition, load balancing or priority-based traffic distribution should be used as the default distribution mode.

[0052] After the round-trip time (RTT) or packet loss rate (PLR) reaches the switching condition, the PMF (Positive Flow Factor) splitting mode switching report message is used to notify the peer that the splitting mode has been switched from the default splitting mode to the redundant splitting mode. When the RTT or PLR recovers to the level before the switching condition, the PMF splitting mode recovery report message is used to notify the peer to return to the default splitting mode.

[0053] Regarding steps (i), (ii), and (iii) above, in the composite traffic splitting mode, when load balancing is used as the default traffic splitting mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of at least one access channel in the 3GPP and non-3GPP access channels reaches the set threshold value. Specifically:

[0054] Before the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of the 3GPP and non-3GPP access channels reaches the switching conditions, load balancing is used as the default traffic offloading mode.

[0055] In the uplink direction, when the UE calculates that the round-trip time (RTT) of at least one access channel or the packet loss rate (PLR) in the uplink direction meets the handover conditions, it sends a PMF traffic splitting mode switching report to the UPF to notify that the uplink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UE copies the data packets, the UPF deduplicates the subsequently received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UPF to reuse the default load balancing mode.

[0056] In the downlink direction, when the UPF calculates that the round-trip time (RTT) of at least one access channel or the packet loss rate (PLR) in the downlink direction meets the handover conditions, it sends a PMF traffic splitting mode handover report to the UE to notify that the downlink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UPF copies the data packets, the UE performs deduplication on the subsequently received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UE to reuse the default load balancing mode.

[0057] Regarding steps (i), (ii), and (iii) above, in the composite traffic offloading mode, when priority-based traffic offloading is used as the default offloading mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of the high-priority access channel in both 3GPP and non-3GPP access channels reaches the set threshold value. Specifically:

[0058] Priority-based traffic offloading mode is adopted before the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of the 3GPP and non-3GPP access channels reaches the handover condition.

[0059] After the UE or UPF calculates that the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of at least one access channel meets the handover conditions, if the high-priority access channel meets the handover conditions, a PMF traffic splitting mode handover report notification is sent to switch the priority-based default mode to the redundancy mode. If the low-priority access channel meets the handover conditions, no PMF traffic splitting mode handover report is sent, the priority-based default mode is maintained, and only the high-priority access channel is used.

[0060] It should be added that: in the composite traffic splitting mode, when the UE receives the PMF traffic splitting mode switching report message sent by the UPF, it can change the traffic splitting mode only in the downlink direction, or change the traffic splitting mode of the bidirectional link at the same time; when the UPF receives the PMF traffic splitting mode switching report message sent by the UE, it can change the traffic splitting mode only in the uplink direction, or change the traffic splitting mode of the bidirectional link at the same time.

[0061] Regarding steps (i), (ii), and (iii) of this embodiment, in conjunction with the appendix... Figure 2 Taking the composite traffic splitting mode with "load balancing" as the default mode as an example, this paper describes the specific process of achieving flexible data splitting under multiple access points:

[0062] 1. The UE requests to establish an MA PDU session. The PCF provides PCC rules, which contain MA PDU session control information. The SMF generates ATSSS rules and N4 rules containing MAR from the received PCC rules. The traffic splitting mode is "composite", and its default mode is "load balancing". The traffic splitting percentage of the 3GPP and non-3GPP access channels is set. The ATSSS rules are sent to the UE, and the N4 rules are sent to the UPF. These rules are used to control traffic splitting, migration and separation in the uplink and downlink directions, respectively.

[0063] 2. The UE and UPF each calculate the RTT or PLR values ​​for the uplink and downlink directions of the 3GPP and non-3GPP access channels using the PMF. When the RTT or PLR values ​​of both links do not exceed the threshold, the uplink and downlink use a load balancing mode. The UE splits the uplink traffic and sends it through both the 3GPP and non-3GPP access channels, and aggregates the downlink traffic received through both the 3GPP and non-3GPP access channels. The UPF aggregates the uplink traffic and splits the downlink traffic.

[0064] 3. The UE calculates through PMF that the RTT or PLR value of at least one access channel exceeds the threshold.

[0065] 4. The UE sends a PMF offloading mode switching report to the UPF, notifying the UPF that the uplink offloading mode will be switched to redundant offloading;

[0066] 5. The UE and UPF perform uplink traffic offloading mode switching. The UE copies the uplink traffic and sends it through 3GPP and non-3GPP access channels, while the UPF performs deduplication. It should be noted that after receiving the PMF traffic offloading mode switching report sent by the UE, the UPF can switch only the uplink traffic offloading mode (as described in this process), or it can switch the uplink and downlink traffic offloading modes to redundant traffic offloading at the same time.

[0067] 6. The UPF calculates through the PMF that the RTT or PLR value of at least one access channel exceeds the threshold.

[0068] 7. The UPF sends a PMF offloading mode switching report to the UE, notifying the UE that the downlink offloading mode will be switched to redundant offloading;

[0069] 8. The UPF and UE perform downlink traffic splitting mode switching. The UPF copies the downlink traffic and sends it through the 3GPP and non-3GPP access channels, while the UE performs deduplication.

[0070] It should be noted that, for simplicity, the diagram does not show that after the performance of the two access channels is restored, the UE and UPF will send a PMF split mode recovery report to notify the user to switch back to the default mode in one or two directions.

[0071] In summary, the method for flexible data splitting under multiple access conditions proposed in this invention can use load balancing or priority-based default splitting mode in composite splitting when network conditions are good, and directly switch to redundant splitting mode by extending existing PMF message notifications when network conditions are poor. It does not require generating new rules and using a dedicated process for distribution, and has the characteristics of traffic aggregation and link backup, achieving a balance between bandwidth and reliability.

[0072] The above specific examples illustrate the principles and implementation methods of the present invention in detail. These embodiments are merely for the purpose of helping to understand the core technical content of the present invention. Based on the above specific embodiments of the present invention, any improvements and modifications made to the present invention by those skilled in the art without departing from the principles of the present invention should fall within the patent protection scope of the present invention.

Claims

1. A method for flexible data splitting under multiple access conditions, characterized in that... Its implementation includes: When establishing the MA PDU session delivery policy, ATSSS rules are sent to the UE and N4 rules are sent to the UPF. The ATSSS and N4 rules include six traffic offloading modes: primary / backup, minimum delay, priority-based, load balancing, redundancy, and composite. The composite traffic offloading mode includes three types: priority-based, load balancing, and redundancy. When the traffic offloading mode is the composite traffic offloading mode, the threshold value of round-trip time (RTT) or packet loss rate (PLR) is set. The UE and UPF respectively calculate the round-trip time (RTT) or packet loss rate (PLR) of the 3GPP and non-3GPP access channels through the PMF. In the composite traffic splitting mode, before the round-trip time (RTT) or packet loss rate (PLR) reaches the switching condition, load balancing or priority-based traffic splitting mode is used as the default traffic splitting mode. After the RTT or PLR reaches the switching condition, a PMF traffic splitting mode switching report message is used to notify the peer that the traffic splitting mode has switched from the default traffic splitting mode to the redundant traffic splitting mode. When the RTT or PLR recovers to the level before the switching condition, a PMF traffic splitting mode recovery report message is used to notify the peer to return to the default traffic splitting mode.

2. The method for flexible data splitting under multiple access conditions according to claim 1, characterized in that, In the composite load balancing mode, if no default load balancing mode is specified, the default load balancing mode with a fixed split ratio of 50% will be used.

3. The method for flexible data splitting under multiple access conditions according to claim 1, characterized in that, In the composite traffic splitting mode, when load balancing is used as the default traffic splitting mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of at least one access channel in the 3GPP and non-3GPP access channels reaches the set threshold value.

4. A method for flexible data splitting under multiple access conditions according to claim 2 or 3, characterized in that, In the composite traffic splitting mode, load balancing is used as the default traffic splitting mode before the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of the 3GPP and non-3GPP access channels reaches the switching conditions. When the UE calculates that the round-trip time (RTT) or uplink packet loss rate (PLR) of at least one access channel meets the handover conditions, it sends a PMF traffic splitting mode handover report to the UPF to notify that the uplink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UE copies the data packets, the UPF deduplicates the subsequent received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UPF to reuse the default load balancing mode. When the UPF calculates that the round-trip time (RTT) or downlink packet loss rate (PLR) of at least one access channel meets the handover conditions, it sends a PMF traffic splitting mode handover report to the UE to notify that the downlink traffic splitting has changed from the default load balancing mode to the redundancy mode. After that, the UPF copies the data packets, the UE performs deduplication on the subsequent received traffic, and before the RTT or PLR of the two access channels (3GPP and non-3GPP) meet the handover conditions, it sends a PMF traffic splitting mode recovery report to the UE to reuse the default load balancing mode.

5. The method for flexible data splitting under multiple access conditions according to claim 1, characterized in that, In the composite traffic splitting mode, when priority-based traffic splitting is used as the default mode, the switching condition is that the round-trip time (RTT) or packet loss rate (PLR) of the high-priority access channel in the 3GPP and non-3GPP access channels reaches the set threshold value.

6. The method for flexible data splitting under multiple access conditions according to claim 5, characterized in that, In the composite traffic splitting mode, priority-based traffic splitting mode is adopted as the default mode before the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of the 3GPP and non-3GPP access channels reaches the handover conditions. After the UE or UPF calculates that the round-trip time (RTT) or packet loss rate (PLR) in the uplink and downlink directions of at least one access channel meets the handover conditions, if the high-priority access channel meets the handover conditions, a PMF traffic splitting mode handover report notification is sent to switch the priority-based default mode to the redundancy mode. If the low-priority access channel meets the handover conditions, no PMF traffic splitting mode handover report is sent, the priority-based default mode is maintained, and only the high-priority access channel is used.

7. A method for flexible data splitting under multiple access conditions according to claim 4 or 6, characterized in that, In the composite traffic splitting mode, when the UE receives the PMF traffic splitting mode switching report message sent by the UPF, it changes the traffic splitting mode in the downlink direction or changes the traffic splitting mode in the bidirectional link.

8. The method for flexible data splitting under multiple access conditions according to claim 7, characterized in that, In the composite traffic splitting mode, when the UPF receives the PMF traffic splitting mode switching report message sent by the UE, it changes the traffic splitting mode in the uplink direction or changes the traffic splitting mode in the bidirectional link.

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