EP-4736525-A1 - SYSTEM AND METHODS FOR FLOW MOBILITY CONTROL

Abstract

A wireless communication method for use in a session management function is disclosed. The method comprises receiving, from a policy control function (PCF), policy and charging control (PCC) rules comprising an association between each QoS flow of a multi-access protocol data unit (MA PDU) session and one of a plurality of accesses of the MA PDU session, and transmitting, to at least one wireless device, at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules.

Inventors

• ZHOU, XINGYUE
• ZHU, JINGUO

Assignees

• ZTE Corporation

Dates

Publication Date

20260506

Application Date

20230721

Claims (20)

1. A wireless communication method for use in a session management function, the method comprising: receiving, from a policy control function (PCF) , policy and charging control (PCC) rules comprising an association between each QoS flow of a multi-access protocol data unit (MA PDU) session and one of a plurality of accesses of the MA PDU session, and transmitting, to at least one wireless device, at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules.
2. The wireless communication method of claim 1, wherein the at least one rule comprises at least one access traffic steering, switching and splitting (ATSSS) rule, and wherein transmitting, to the at least one wireless device, the at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules comprises: transmitting, to a wireless terminal, the at least one ATSSS rule.
3. The wireless communication method of claim 1 or 2, wherein the at least one rule comprises at least one N4 rule, and wherein transmitting, to the at least one wireless device, the at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules comprises: transmitting, to a user plane function (UPF) , the at least one N4 rule.
4. The wireless communication method of any of claims 1 to 3, wherein at least two accesses in the plurality of accesses have the same access type and/or the same radio access technology (RAT) type.
5. The wireless communication method of any of claims 1 to 4, wherein the association between each QoS flow of the MA PDU session and one of the plurality of accesses of the MA PDU session comprises an association between each QoS flow of the MA PDU session and an access node of one of the plurality of accesses of the MA PDU session.
6. The wireless communication method of any of claims 1 to 5, further comprising: transmitting, to the PCF, a session management policy control create message for the MA PDU session, wherein the session management policy control create message indicates at least one access type and/or at least one RAT type of the plurality of accesses.
7. The wireless communication method of claim 6, further comprising: receiving, from an access and mobility management function (AMF) , a session management context create message for the MA PDU session, wherein the session management context create message comprises information associated with the plurality of accesses.
8. The wireless communication method of claim 7, wherein the information associated with the plurality of accesses comprises at least one of: an indication of whether a wireless terminal of the MA PDU session registers over at least two of the plurality of accesses, an access type of each access over which the UE registers, or a radio access technology (RAT) type of each access over which the UE registers.
9. A wireless communication method for use in a policy control function (PCF) , the method comprising: transmitting, to a session management function (SMF) , policy and charging control (PCC) rules comprising an association between each QoS (quality of service) flow of a multi-access protocol data unit (MA PDU) session and one of a plurality of accesses of the MA PDU session.
10. The wireless communication method of claim 9, wherein at least two accesses in the plurality of accesses have the same access type and/or the same radio access technology (RAT) type.
11. The wireless communication method of claim 9 or 10, wherein the association between each QoS flow of the MA PDU session and one of the plurality of accesses of the MA PDU session comprises associations between each QoS flow of the MA PDU session and an access node of one of the plurality of accesses of the MA PDU session.
12. The wireless communication method of any of claims 9 to 11, further comprising: receiving, from the SMF, a session management policy control create message for the MA PDU session, wherein the session management policy control create message indicates at least one access type and/or at least one RAT type of the plurality of accesses.
13. A wireless communication method for use in an access and mobility management function (AMF) , the method comprising: transmitting, to a session management function, a session management context create message for a multi-access protocol data unit (MA PDU) session, wherein the session management context create message comprises information associated with a plurality of accesses of the MA PDU session.
14. The wireless communication method of claim 13, wherein the information associated with the plurality of accesses comprises at least one of: an indication of whether a wireless terminal of the MA PDU session registers over at least two of the plurality of accesses, an access type of each access over which the UE registers, or a radio access technology (RAT) type of each access over which the UE registers.
15. The wireless communication method of claim 13 or 14, further comprising: receiving, from a wireless terminal of the MA-PDU session, an establishment request for the MA PDU session, wherein the establishment request comprises an indication of supporting an MA PDU session via a plurality of accesses having the same access type and/or the same radio access technology (RAT) type.
16. A wireless communication method for use in a wireless terminal, the method comprising: receiving, from a session management function (SMF) , at least one access traffic steering, switching and splitting (ATSSS) rule which comprises at least one quality of service (QoS) flow of a multi access protocol data unit (MA PDU) session and is determined based on policy and charging control (PCC) rules comprising an association between each QoS flow of the MA PDU session and one of a plurality of accesses of the MA PDU session, and selecting at least one QoS flow for transmitting uplink traffic of the MA PDU session based on the at least one ATSSS rule.
17. The wireless communication method of claim 16, wherein at least two accesses in the plurality of accesses have the same access type and/or the same radio access technology (RAT) type.
18. The wireless communication method of claim 16 or 17, wherein the association between each QoS flow of the MA PDU session and one of the plurality of accesses of the MA PDU session comprises an association between each QoS flow of the MA PDU session and an access node of one of the plurality of accesses of the MA PDU session.
19. The wireless communication method of any claims 16 to 18, further comprising: transmitting, to an access and mobility management function, an establishment request for the MA PDU session, wherein the establishment request comprises an indication of supporting an MA PDU session via a plurality of accesses having the same access type and/or the same radio access technology (RAT) type.
20. A wireless device, comprising: a communication unit, configured to: receive, from a policy control function (PCF) , policy and charging control (PCC) rules comprising an association between each QoS flow of a multi-access protocol data unit (MA PDU) session and one of a plurality of accesses of the MA PDU session, and transmit, to at least one wireless device, at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules.

Description

SYSTEM AND METHODS FOR FLOW MOBILITY CONTROL TECHNICAL FIELD This document is directed generally to wireless communications and in particular to 5G communications. BACKGROUND In the existing art, the term “ATSSS” refers to access traffic steering, switching and splitting. This feature can be supported by a UE (user equipment) and a 5GC (5G Core) network enabling a multi-access PDU (protocol data unit) connectivity service, which can exchange PDUs between the UE and a data network by simultaneously using one 3GPP (3rd generation partner project) access network and one non-3GPP access network and two independent N3/N9 tunnels between a PSA (PDU session anchor) and a RAN/AN (radio access network/access network) . The multi-access PDU connectivity service is realized by establishing a multi-access PDU (MA PDU) session, i.e., a PDU session that may have user-plane resources on two access networks. The UE may request an MA PDU session when the UE is registered via both the 3GPP and non-3GPP accesses or when the UE is registered via one access only. After an establishment of the MA PDU session and when there are user-plane resources on both access networks, the UE applies network-provided policy (i.e., ATSSS rules) and considers local conditions (such as network interface availability, signal loss conditions, user preferences, etc. ) for deciding how to distribute uplink traffic across the two access networks. Similarly, the UPF (user plane function) anchor of the MA PDU session applies network-provided policy (i.e., N4 rules) and feedback information received from the UE via the user-plane (e.g., access network unavailability or availability) for deciding how to distribute downlink traffic across the two N3/N9 tunnels and two access networks. When there are user-plane resources on only one access network, the UE applies the ATSSS rules and considers local conditions for triggering the establishment or activation of the user plane resources over another access. The type of the MA PDU Session may be one of the following types: IPv4, IPv6, IPv4v6, and Ethernet. FIG. 1 shows an architecture with ATSSS support in the existing 5GS (5G system) . In FIG. 1: - The UE supports one or more of the steering functionalities, e.g., MPTCP functionality and/or ATSSS-LL functionality. Each steering functionality in the UE enables traffic steering, switching and splitting across 3GPP access and non-3GPP access, in accordance with the ATSSS rules provided by the network. The ATSSS-LL functionality is mandatory in the UE for MA PDU session of type Ethernet. - The UPF may support MPTCP Proxy functionality, which communicates with the MPTCP functionality in the UE by using the MPTCP protocol (see IETF RFC 8684) . - The UPF may support ATSSS-LL functionality, which is similar to the ATSSS-LL functionality defined for the UE. There is no user plane protocol defined between the ATSSS-LL functionality in the UE and the ATSSS-LL functionality in the UPF. The ATSSS-LL functionality in the UPF is not shown in FIG. 1. - In addition, the UPF supports Performance Measurement Functionality (PMF) , which may be used by the UE to obtain access performance measurements over the user-plane of 3GPP access and/or over the user-plane of non-3GPP access. SUMMARY This document relates to methods, systems, and devices for flow mobility control, and in particular to methods, systems, and devices for flow mobility control over multiple accesses networks. The present disclosure relates to a wireless communication method for use in a session management function. The method comprises: receiving, from a policy control function (PCF) , policy and charging control (PCC) rules comprising an association between each QoS flow of a multi-access protocol data unit (MA PDU) session and one of a plurality of accesses of the MA PDU session, and transmitting, to at least one wireless device, at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules. Various embodiments may preferably implement the following features: Preferably, the at least one rule comprises at least one access traffic steering, switching and splitting (ATSSS) rule. Preferably, transmitting, to the at least one wireless device, the at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules comprises: transmitting, to a wireless terminal, the at least one ATSSS rule. Preferably, the at least one rule comprises at least one N4 rule. Preferably, transmitting, to the at least one wireless device, the at least one rule which comprises at least one QoS flow of the MA PDU session and is determined based on the PCC rules comprises: transmitting, to a user plane function (UPF) , the at least one N4 rule. Preferably, at least two accesses in the plurality of accesses have the same access type and/or the same radio access technology (RAT) type. Preferably, the association between each QoS flow of