Abstract
Epidemic routing protocol (ERP) had been widely studied and applied to the Delay Tolerant Networks (DTNs). In DTNs, the delay of packets is long due to the intermittent connections cause by the mobility of nodes. However, ERP can reduce the delay time and raise the packet delivery rate by replicating and spread several copies of a source packet into the network, but inevitably exhaust enormous memory resources and network bandwidth. We propose a network coding with limited buffer routing protocol (NC-LB) in this thesis. NC-LB improves the performance of ERP in many-to-one communications in DTNs when the buffer size is limited. When the buffer of a node is full, two packets in the buffer are randomly chosen and be linearly encoded together in to a packet to save buffer space. From our analysis, the converging time of NC-LB is equal or lower than ERP, NC-LB even saves more than 70% converging time than ERP when the source node number to buffer size ratio is high. The simulation results conform to the analysis that NC-LB outperforms ERP in DTNs for many-to-one model with limited buffer size