Terminal Session Release for Network Slice Handover
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During cell handover in communication networks, existing methods face challenges in quickly releasing sessions for unsupported network slices, leading to latency issues and resource inefficiencies, especially for services sensitive to latency interruptions.
Innovation Solution
A communication method where a terminal device sends a session release request to a network device for unsupported network slices during handover, including an identifier of the target cell, allowing for quick release of unsupported sessions and continuation of supported sessions, thereby optimizing resource usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal device uses core network to control cell handover, then the handover can be performed, but the latency is large and it is difficult to satisfy latency requirements of latency-sensitive services
Solution Approach 1:
The patent segments the handover control function into two parts: (1) RRC connection reconfiguration for basic handover control remains with the access network device, and (2) PDU session release control is separately managed by the terminal device based on slice availability. This segmentation allows the terminal to quickly release sessions for unsupported slices without waiting for core network approval, reducing handover latency while maintaining reliability.
Solution Approach 2:
The terminal device performs preliminary actions by proactively releasing PDU sessions for unsupported network slices before or during the handover process. By including the target cell ID and slice information in the session release request, the terminal prepares the network for upcoming handover, enabling faster session release without waiting for core network processing.
2Reliability
If the terminal device reselects cell and reregisters to network when moving to cell that does not support slice service, then the session can be maintained, but the process is time-consuming and interrupts service
Solution Approach 1:
The terminal device performs preliminary action by proactively releasing PDU sessions for unsupported slices before service interruption occurs. By sending the session release request with target cell ID and slice information during handover, the terminal prevents service interruption rather than recovering from it, maintaining session continuity for supported slices while quickly releasing unsupported ones.
Solution Approach 2:
The patent extracts the PDU session release function from the traditional cell reselection and reregistration process. Instead of maintaining all sessions and then recovering from interruption, the terminal extracts and releases only the sessions for unsupported slices, keeping supported sessions active without interruption.
3Reliability
If the network maintains sessions for all slices during handover, then session continuity is ensured, but network resources are wasted on unsupported slices
Solution Approach 1:
The patent applies local quality by making the session maintenance status slice-specific rather than uniform for all slices. The terminal device identifies which slices are supported by the target cell and releases only those sessions, while maintaining sessions for supported slices. This localized approach ensures session continuity where needed while eliminating resource waste for unsupported slices.
Solution Approach 2:
The patent changes the parameter of session status from a global binary state (maintained/released) to a slice-specific state determined by target cell slice support. By including slice information and target cell ID in the session release request, the system dynamically adjusts session maintenance based on local network conditions, optimizing resource usage while maintaining continuity.
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
This application discloses a communication method and an apparatus. When a terminal device switches to a target cell or is connected to a new primary cell, by requesting a network device to release a session corresponding to a network slice that is not supported by the target cell or the new primary cell and to keep a session corresponding to a network slice that is supported by the target cell or the new primary cell, the session corresponding to the network slice that is not supported by the target cell or the new primary cell can be quickly released, and a network resource is saved while a session corresponding to a network slice supported by the target cell or the new primary cell is enabled to be continued.