An adaptive cross-layer routing protocol for delay-sensitive applications over MANETs

In this paper, we present an adaptive delay-aware multipath routing (ADAMR) framework for reliable transmission of delay-sensitive applications over mobile ad-hoc networks (MANETs). The proposed method uses cross-layer design to abstract the Quality-of-Service (QoS) constraints of requesting applications in terms of end-to-end delay. To ensure that each admitted data session packet gets the required delay, we use an adaptive flow admission control technique. The proposed admission control procedure admits only those data sessions for which our multipath routing protocol is able to find a delay-aware route. Proposed multipath routing protocol not only discovers routes that satisfy the given delay constraints, but also makes sure that the discovered routes are node-disjoint. When a link break is detected on an active route, we use backup route to bypass another overhead generating route discovery process. Extensive simulations prove the effectiveness of the proposed approach under various network scenarios. We use H.264/SVC encoded video traces to model the video source nodes in the network. The proposed method provides required QoS guarantees and perform congestion control based on the current network load levels. It is also observed from simulation results that ADAMR performs accurate admission control and discovers stable multiple node-disjoint routes with minimal routing overhead.