Research And Implementation On Multi-AP Handover Optimization In Home Network Based On FTTR

With the development of WiFi network,people put forward higher and higher requirements for the bandwidth and delay of network service.For home networks,the latest FTTR(Fiber To The Room)networking method begins to spread.Every room in the user's home exists an AP,and the users move frequently around the rooms in home,which will cause wireless handover.However,wireless handover in the current FTTR scenario exists handover delay and high packet loss rate,which also has a great adverse effect on the throughput.It's very necessary to optimize the handover quality to meet the user's demand for the quality of the network service of large traffic and high real-time.First,the thesis points out the problem of hadover delay in the current FTTR networking,and analyzes the limitations of the current technical solutions.Then,combining with the latest WIFI6 characteristics and the characteristics of network services under the FTTR scenario,the multi-AP single-BSSID networking scheme is proposed.By using multiple APs with the same BSSID,the STA does not execute the normal switching process.With the APs sharing the associated information,the STA completes the fast and non-inductive switching.The test result showed that this scheme can effectively reduce the AP switching delay in the handover process.Next,the thesis analyzes the problem of packet loss and throughput degradation in FTTR scenarios,and concludes that the STA moves to the edge of AP before handover,STA will offline for a short time during handover,and the AP cannot submit handover packets normally,which results in packet loss and time delay during handover.The packet loss in handover causes the TCP sender to slow down,resulting in a decrease in network throughput.The design of the thesis makes full use of the resources of the home gateway,and introduces a “buffer and forward” solution in handover scenarios to solve the problem of the downlink packet loss;introduces the unconditional submission of the uplink for the AP to solve the the problem of uplink packet loss;proposes the idea that gateway perform TCP proxy retransmission and fast recovery.The gateway replaces the TCP receiver to acknowledge the TCP segments to the TCP sender in advance and speeds up congestion recovery,which reduces the transmission burden on the sender and avoids a significant drop in TCP throughput.Finally it was developed in the Linux development environment,and the test environment was set up.The test results showed that the handover performance was optimized.