WLAN中一种基于负载平衡的AP切换机制

针对高密度大流量的无线局域网,提出了一种快速可靠的平衡负载的AP切换机制,采用中心结构,即当某无线接入点(AP)的负载超过阈值时,由该AP强制触发切换．综合利用其邻接AP的负载信息和无线终端(MH)接收的邻接AP的信噪比(SNR),计算ISL函数,以选择需要切换的MH及其目标AP．实验表明:与IEEE 802．11协议相比,整个系统的吞吐量提高了50%左右,部分MH的吞吐量提高了2倍多,而且媒体接入的延迟也大大减小．

A Load-Based AP Handoff Algorithm for WLAN

For high density and large traffic WLAN environment,we have presented a reliable AP handoff mecha- nism based on load balance.We used center structure:when an AP's load exceeded the load threshold,the AP started up force handoff.Using the loads of neighboring APs and the SNRs collected by mobile host,the algorithm calculates the function ISL,chose the handoff mobile host and its new AP.Experiment results have shown that,compared with IEEE 802.11 protocol,the system's throughput was raised by up to 50%,some mobile host's throughput is even twice more than before,and the media access delays of most APs reduce greatly.