SSR: Segment-by-Segment Routing in Large-Scale Mobile Ad Hoc Networks

Location-based routing in mobile ad hoc networks (MANETs) does not need to use pre-computed routes for forwarding packets thus scales very well. However, location-based routing suffers from two major problems: hole-induced local optimum and mobility-induced location errors. To solve these problems, in this paper, we propose a segment-by-segment routing (SSR), which is a combination of location-based routing and topology-based routing. It maintains a k-hop vicinity routing table for each cluster head (CH), and uses location-based routing between neighboring k-hop vicinities while applies topology-based routing in the k-hop vicinity. The k-hop vicinity routing table provides useful reachability information used by an avoidance-based strategy to deal with holes, and helps to achieve the degree of tolerance of location inaccuracy with k-hop long radio transmissions. Comparative analysis shows that the proposed protocol outperforms the well-known GPSR routing protocol in terms of reliability, tolerance of location inaccuracy, and communication complexity, with a little larger cost in control messages