A Unicast MANET Routing Protocol to Simultaneously Minimize the Stability-Hop Count Tradeoff and End-to-End Delay

The high-level contribution of this paper is the design and development of a unicast routing protocol to effectively minimize the stability-hop count tradeoff observed in mobile ad hoc networks (MANETs) and thereby incur lower end-to-end delay per data packet. The proposed unicast routing protocol, referred to as SILET, uses the predicted link expiration times (LETs) as part of the link weights. SILET is a source-initiated on-demand routing protocol that initiates a global broadcast query-reply cycle to discover routes, the destination chooses the route with the lowest sum of the link weights, the weight assigned to a link is '1' plus the inverse of the LET of the link. The term '1' as part of the link weight minimizes the hop count per path and the term comprising of the inverse of the LET maximizes the lifetime of the routes. Through extensive simulations and comparison with contemporary minimum-hop based and stability-based routing protocols, we demonstrate that SILET discovers long-living stable routes with hop count close to that of the minimum, thus, minimizing the stability-hop count tradeoff. By virtue of incurring lower route discovery control overhead (due to long-living stable routes) and lower hop count per route, the end-to-end delay per data packet is also optimized and has been observed to be the lowest among all the routing protocols simulated in this paper.