Spray and Wait+ : An Efficient Routing Scheme for Intermittently Connected Mobile Networks
DTN stands for Disruption/Delay Tolerant Network, which is a kind of wireless network that provides a promising solution to address issues in regions where at the relay time of the message, a contiguous path which is node-to- node, that links together they said sender and said receiver, doesn't persist. Such networks are sporadically linked mobile networks which are discontinuous wireless/radio networks. The end nodes have finite power or memory resources; hence network connectivity may not be available or lack continuously. Both nodes and corresponding links connecting them may have lasting disconnections and be inherently capricious. DTN provides assured data delivery as the intermediary nodes on the transmission path use Store and Forward technique (SFT). To execute the DTN framework, paths have to be established over several unreliable connected hops at regular interims. Even though flood-based schemes have an elevated delivery probability, they endure severe contention and consume heaps of energy, which can significantly deteriorate their performance. Moreover, proposed attempts to remarkably minimize the overhead of flood-based schemes have often been afflicted by large delays. Subsequently came the Spray & Wait scheme which “sprays” 'x' number of message copies in the lattice, and subsequently “waits” till any one of the nodes carrying the message copy meets the end-destination. This paper shows a change of the at present existing Binary Spray &Wait routing protocol where the spray/spritz phase has been tweaked. The test simulation results help us in conceding that this modification leads to higher probability of delivery and lower average latency and overhead ratio.
Keywords - DTN, Spray and Wait, Delivery probability, Average latency, Overhead ratio