PDU Session Handover Determination Using Region Lists
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In next-generation mobile communication, the handover procedure for Packet Data Unit (PDU) sessions in Local Area Data Networks (LADN) is inefficient, leading to unnecessary resource wastage due to the inability to accurately determine whether a PDU session is intended for LADN, resulting in incorrect handovers and resource reservation issues.
Innovation Solution
A method for determining a target cell or Next Generation Radio Access Network (NG-RAN) for handover based on measurement reports, using a handover region list to confirm if the target can service the PDU session, and transmitting a handover request message without context if the target is unable to service it, thereby optimizing handover procedures and resource management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If handover procedure for PDU sessions in LADN is performed without accurate determination of service region, then handover processing is simplified, but unnecessary handovers occur leading to resource wastage
Solution Approach 1:
The network configures the UE with a handover region list during PDU session establishment or update, before handover occurs. This preliminary configuration enables the UE to autonomously determine whether a target cell is within the allowed handover region, preventing unnecessary handovers before they happen and avoiding the associated resource wastage while maintaining simple handover processing
2Measurement precision
If handover region list is configured for each PDU session, then handover accuracy is improved, but device complexity increases
Solution Approach 1:
Instead of implementing complex network-side determination mechanisms, the network creates a simplified copy of the handover region information (as a list of allowed cells or tracking areas) and provides it to the UE. The UE then uses this copied information for autonomous handover determination, achieving accurate handover control without increasing device complexity
3Speed
If target cell selection is based only on measurement reports, then handover speed is improved, but handover correctness deteriorates due to inability to verify LADN service availability
Solution Approach 1:
The handover region list is configured in advance during PDU session establishment or update, enabling the UE to perform rapid handover decisions based on both measurement reports and the pre-configured region list. This preliminary configuration maintains handover speed while ensuring correctness by filtering out invalid target cells before handover execution
Solution Approach 2:
The handover region list acts as an intermediary between the measurement report (speed factor) and the handover decision (correctness factor). It provides a simple lookup mechanism that quickly determines whether a measured target cell is valid for LADN service, maintaining fast handover execution while ensuring service availability
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A disclosed feature of the present specification provides a method for a source cell determining a handover of a packet data unit (PDU) session. The method may include a step of determining a target cell or target next generation radio access network (NG-RAN) based on a measurement report by a terminal. A handover region list can additionally be considered in the target cell or target NG-RAN determination step. The method may include a step of transmitting a handover request message that does not include context with respect to the PDU session to the target cell or target NG-RAN, based on the handover region list, if it is confirmed that the determined target cell or target NG-RAN cannot serve for the PDU session.