AP Multi-Link Roaming Buffer Transfer to Reduce Packet Loss

Solution Overview

Problem

Packet loss occurs during the roaming process of non-AP MLDs due to link quality degradation, affecting communication reliability.

Innovation Solution

Implement a method where the current AP MLD transfers data from its send buffer to the non-AP MLD or target AP MLD before the non-AP MLD roams, and manage block acknowledgement (BA) session information and keys to ensure seamless handover.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the non-AP MLD roams to a target AP MLD to improve link quality, then communication quality is improved, but packet loss occurs during the roaming process

Engineering Contradiction:

Improvecommunication reliabilityVSAvoidpacket loss

Core Design Contradiction:

ReliabilityVSLoss of information

Solution Approach 1:

The current AP MLD performs preliminary data transfer by sending buffered data to the target AP MLD before the non-AP MLD completes the roaming handover. This advance action ensures that data is already available at the target AP MLD when the non-AP MLD switches connections, eliminating packet loss during the transition.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The target AP MLD acts as an intermediary to receive and forward data during the roaming process. The current AP MLD sends data to the target AP MLD, which then forwards it to the non-AP MLD, ensuring continuous data delivery without interruption during the handover transition.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Device complexity

If the current AP MLD clears the send buffer during roaming, then device complexity is reduced, but data continuity is lost

Engineering Contradiction:

Improvebuffer management complexityVSAvoiddata continuity

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

The current AP MLD performs preliminary data transfer by sending buffered data to the target AP MLD before the non-AP MLD completes the roaming handover. This advance action ensures that data is already available at the target AP MLD when the non-AP MLD switches connections, eliminating packet loss during the transition.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The target AP MLD acts as an intermediary to receive and forward data during the roaming process. The current AP MLD sends data to the target AP MLD, which then forwards it to the non-AP MLD, ensuring continuous data delivery without interruption during the handover transition.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20260067773A1Communication method and apparatus

Publication Date: 2026.03.05 HUAWEI TECH CO LTD

AI summary

A communication method and apparatus are provided. The method includes, when a current access point multi-link device (AP MLD) determines that a non-AP MLD roams from the current AP MLD to a target AP MLD, and data exists in a send buffer (the send buffer is used to buffer data of the current AP MLD and data of the non-AP MLD) of the current AP MLD, the current AP MLD may send all the data in the send buffer to the non-AP MLD, or the current AP MLD may send all the data in the send buffer to the target AP MLD, so that the non-AP MLD can receive, from the target AP MLD, the data from the current AP MLD. This reduces a packet loss in a roaming handover process of the non-AP MLD, and further improves communication reliability of the non-AP MLD in the roaming process.