Routing Protocol Based On Network Coding For Sensor Networks Probability Analysis

Traditionally, nodes just route and forward packets. Network coding is proposed to change this situation. With network coding, nodes can code the packets before forwarding, this improvement be able to enhance network throughput. Furthermore, through network coding, we can obtain the benefits of saving in bandwidth, load balancing, improving reliability and so on. Because the nodes in the Wireless Sensor Network (WSN) have limited resource, so the traditional routing protocol isn't fit for it. Probabilistic routing can be used in the WSN due to the following reasons: optional message forwarding, strong fault-tolerance and it doesn't need to know the whole network topology.This paper applies network coding to the probabilistic routing. Then, proposes an analytical framework to study the performance of probabilistic routing based on network coding, in comparison with probabilistic routing based on replication. On the basis of the probabilistic routing, combines with network coding and refers to the thinking of single copy, Spray and Wait routing, we proposes an improvement protocol: Extended Probabilistic Routing base Network Coding (EXPR-NC) in which nodes directly forward packets without copying and establish a neighboring nodes list for each node. The goal of this protocol is keep the advantage of network coding and reduce the redundancy simultaneously.We establish an analytical model for each protocol, then, give out three criterions: Delivery delay, reliability and redundancy. The analysis result shows that network coding can decrease Delivery delay and increase reliability based on the certain redundancy, especially when buffer and bandwidth are restricted. But at the same time, network coding brings redundancy. In order to reduce the redundancy, this paper proposes EXPR-NC, as the result of the analysis, we know that EXPR-NC can not only greatly decrease redundancy but also decrease Delivery delay and increase reliability. So we gain the results that EXPR-NC promotes the general performance, and then proves the results through the simulation.