Abstract:

Existing opportunistic routing protocols that joint network coding assume that wireless link transmissions are independent, but related studies have shown that wireless link transmissions are correlated. Link correlation affects the number of times the forwarder transmit the encoded packet and the selection of the forwarders, which in turn affects the performance of the protocol. In this paper, an opportunistic routing mechanism considering link correlation in intra-session network coding is proposed. In the mechanism, a node periodically collects feedback information of neighbor nodes to measure link correlation, and thus accurately calculates the expected number of forwarding times and selects the forwarder set with fewer transmissions. Simulation experiments have shown that this mechanism can significantly reduce the transmission redundancy in the network and improve the overall throughput of the network.

Key words: intra-flow network coding, link correlation, transmission calculating, forwarder selection

摘要：

现存的结合网络编码的机会路由协议假设无线链路传输是相互独立的，但是相关研究表明无线链路传输具有相关性。链路相关性会影响节点转发编码包的次数以及转发节点的选取，进而降低协议的性能表现。对此，提出了一种流内编码中考虑链路相关性的机会路由机制。在该机制中，节点周期性收集邻居节点的反馈信息以衡量链路相关性，并由此准确计算节点期望转发次数进而选取总转发次数更少的转发节点集合。仿真实验表明，该机制能显著降低网络中的发送冗余，提高网络的整体吞吐量。

关键词: 流内网络编码, 链路相关性, 传输计算, 转发节点选取