PDCP Layer Communication Mode Switching for Lossless Handover
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Solution Overview
Problem
Existing communication systems face challenges in seamlessly switching communication modes for user equipment (UE) as it moves between cells with different multicast capabilities, leading to potential service disruptions and inefficiencies.
Innovation Solution
A communication mode switching method is introduced, where a Packet Data Convergence Protocol (PDCP) data transmission status is sent from a first network device to a second network device, allowing the second network device to switch to a second communication mode and ensure continuous PDCP sequence numbers, thereby achieving lossless switching.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If communication mode switching is implemented in existing systems, then service continuity can be maintained during UE mobility, but service disruptions and inefficiencies occur due to lack of seamless switching between cells with different multicast capabilities
Solution Approach 1:
The source access network device forwards PDCP data packets to the target access network device before the UE completes mode switching. This preliminary action ensures that the target device has the necessary data ready, enabling seamless transition without service disruption or efficiency loss
2Device complexity
If communication mode switching is performed without PDCP layer implementation, then switching can be simpler, but PDCP sequence number continuity cannot be ensured leading to data loss
Solution Approach 1:
The PDCP layer acts as an intermediary between the upper layers and the communication mode switching mechanism. It maintains sequence number continuity by forwarding packets with proper sequencing, ensuring no data loss while managing the complexity of mode switching between unicast and multicast
Data Source
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AI summary
Provided are a communication mode switching method, and an apparatus and a device. The method comprises: a first network device sending a PDCP data sending state of a user equipment in a first communication mode to a second network device; and the second network device issuing a service to the user equipment by means of a second communication mode and according to the PDCP data sending state. According to the present application, a PDCP data sending state of a user equipment in a first communication mode is switched into a second communication mode to receive and send a service, such that communication mode switching is realized at a PCDP layer, and the continuity of PDCP serial numbers is ensured, thereby realizing lossless switching, and reducing the switching delay.