PDU Session Reestablishment for Priority-Based Network Slice Switching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mobile communication technologies face challenges in efficiently switching an established Packet Data Unit Session (PDU Session) to a dedicated Network Slice Instance (NSI) when a user's service priority changes, particularly for high-priority users or services, to enhance Quality of Service (QoS) assurance.
Innovation Solution
A method and system that involves an Application Function (AF) sending service priority change information to a Policy Control Function (PCF), which then coordinates with other network entities like the Session Management Function (SMF), Access and Mobility Management Function (AMF), and Network Slice Selection Function (NSSF) to modify the S-NSSAI and reestablish the PDU Session to an appropriate NSI, ensuring the new PDU Session aligns with the updated priority.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a normal-priority user has established a PDU Session, then the service experience of normal users is ensured, but when the user's service priority changes to high-priority, the system cannot automatically switch the PDU Session to a dedicated NSI, resulting in poor QoS assurance
Solution Approach 1:
The system implements a feedback mechanism where the AF sends service priority change information to the PCF, which then triggers a sequence of notifications and updates throughout the network. The PCF notifies the SMF to deactivate the old PDU Session, and the system monitors and detects priority changes to initiate the switching process automatically
Solution Approach 2:
The system dynamically adapts to changing service priorities by modifying the PDU Session based on real-time priority information. When priority changes are detected, the system transitions from a static normal-priority configuration to a dynamic high-priority configuration with dedicated NSI resources, allowing the network to respond flexibly to varying service requirements
2Reliability
If the system deactivates and reestablishes the PDU Session to switch to a dedicated NSI, then QoS assurance is improved, but the service interruption and time delay increase
Solution Approach 1:
The system performs preliminary actions by having the AF send service priority change information to the PCF before the actual session switch is needed. The PCF proactively notifies the SMF about the upcoming priority change, allowing the network to prepare resources in advance. The AMF also proactively seeks service authorization from the PCF before the PDU Session is fully deactivated
Solution Approach 2:
The system accelerates the session switching process by streamlining the notification and authorization flows. The PCF directly notifies the SMF to deactivate the PDU Session without unnecessary intermediate steps, and the AMF quickly obtains service authorization from the PCF. The system rushes through the critical path of session switching to minimize interruption time
Data Source
AI summary
A method and system for adjusting a service priority of a user, and a storage medium are provided. The method for adjusting a service priority of a user includes: an AF sends service priority change information of UE to a PCF; the PCF notifies an SMF corresponding to an activated PDU Session to deactivate a PDU Session activated by the UE, and to notify the UE to reestablish a PDU Session; an AMF receives a PDU Session establishment request sent by the UE and sends a service authorization request message to the PCF; the PCF modifies a first S-NSSAI into a changed S-NSSAI corresponding to the service priority change information, sends a service authorization response message to the AMF, and establishes a new PDU Session for the UE, wherein an S-NSSAI of the new PDU Session is the changed S-NSSAI.