A Handoff-based And Limited Flooding (HALF) Routing Protocol in Delay Tolerant Network (DTN)

In a Delay Tolerant Network (DTN), routing protocols are developed to manage the disconnected mobile nodes. We propose a routing protocol named HALF (Handoff-based And Limited Flooding) in DTN that can work in both infra-structured and infra-structure less networking environment and hence it can improve the performance of the network significantly. In this paper, it is shown that HALF gives satisfactory delivery ratio and latency under almost all conditions and different network scenarios when compared to the other existing DTN routing protocols. As the traffic intensity of the network grows from low (.2) to high (.75) values, HALF shows about 5% decrease in the delivery ratio compare to much larger values showed by the other routing protocols and on the average takes same time to deliver all the messages to their destinations. As the radio range is increased over the range from 10m Bluetooth range to 250m WLAN range, due to the increased connectivity, the delivery ratio and the latency are increased by 4 times and decreased by 5 times respectively.