A reliable data transfer protocol based on twin paths and network coding for underwater acoustic sensor network

MPNC (multiple path and network coding) is proposed as a reliable transport protocol for UWASN (underwater acoustic sensor network). In MPNC, after three disjoint paths being established, two groups of packets (A and B), coded by network coding, are transmitted over the two side paths respectively, and another group of packets C = A⊕ B are transmitted over the middle path. That is, any two paths can work together as a redundant path for another path, and the reliable transmission of one packet can be guaranteed by 1.5 packets. In order to reduce the number of redundant packets without affecting the transmission reliability, the packets of group C are coded further at special ratio by network coding as shareable redundant packets according to the link error, and a reliable transport protocol TPNC (twin path and network coding) based on two paths and network coding is proposed in this paper. In TPNC, after two disjoint paths, called twin paths, being established, two groups of packets (A and B), coded by network coding, are transmitted with their own shareable redundant packets over the two paths respectively to guarantee the data packet transmission reliability. The results of simulations show that, compared with MPNC, TPNC can acquire similar data delivery ratio with lower energy consumption.