一种基于网络编码的速率自适应多播MAC协议

针对现有IEEE 802.11协议在无线局域网多播应用中存在可靠性差、吞吐性能不佳等诸多缺陷,提出了一种基于网络编码的速率自适应多播MAC协议RAMPNC.该协议采用网络编码组传输模型发送多播数据,使多播接收节点通过对累积的编码帧进行解码操作恢复出所需的原始数据.此外,RAMPNC利用RTS/CTS 握手信号实现信道状态信息交换,并根据多播接收节点反馈的信道信噪比估值动态调整源端的物理层发送速率.通过使用NS-2模拟器评估RAMPNC协议性能,结果显示,该协议在多播吞吐量,平均帧传输延时和帧投递率等方面获得了比已有ELBP和ARSM协议更好的性能.

A Rate Adaptive Multicast MAC Protocol Based on Network Coding

In order to overcome the deficiency of the multicast service provided by IEEE 802.11, a rate adaptive multicast MAC protocol based on network coding called RAMPNC was proposed for the Wireless Local Area Network (WLAN). RAMPNC exploited network coding group to transmit multicast data frames. And the original data were decoded from combined frames in multicast nodes. Furthermore, the channel state information was obtained through RTS-CTS signal exchange. The RAMPNC could adjust the physical sending rate according to the estimated SNR that was feedbacked by multicast nodes. NS - 2 simulator was used to evaluate the performance of the RAMPNC protocol. The result has showed that RAMPNC can achieve better performance than existing ELBP and ARSM protocols in terms of multicast throughput, average frame transmission delay and frame delivery rate, etc.