Analyzing and designing energy efficient routing protocol in delay tolerant networks

Delay tolerant networks (Barun Saha, http://delay-tolerant-networks.blogspot.in ) are the networks that address the technical issues in heterogeneous network that may lack continuous network connectivity. A message is forwarded to a node if it has higher delivery predictability than the current node for that particular destination. But there obviously exists a tradeoff between delivery delay and energy consumption (Yoon et al. in Tradeoff between energy consumption and lifetime in delay-tolerant mobile network, 2008), as a message (or a file) has to be delivered to each of several destinations by epidemic relaying. With every relay due to the various nodes, energy is consumed by the node. This adds to the total energy spent in relaying and thus increases the network overhead. As the energy available to a particular node is limited, there is a need to conserve this energy. This paper investigates the Energy Aware Prophet protocol and the methods to optimize the delivery probability. Threshold Algorithm and Remaining Required Energy Algorithm (Kaviani et al. in Delay tolerant routing protocols for energy-neutral animal tracking, 2015) leads to an increase of about 42% in delivery probability and energy is saved by 47%. Also, we have found that the Threshold Algorithm leads to the optimal energy value (i.e. threshold value) as 49 J as a constraint to the current energy. Further, a buffer size higher than 8 M is not recommended, as the delivery probability remains constant after 8 M buffer size.