SCAR: A dynamic Coding-Aware Routing protocol

Traditional wireless routing protocols do not take into account the possibility of network coding. A series of routing protocols are specifically designed to exploit the power of network coding. However, they mostly focus only on initial route set-up but neglect further maintenance. New flows coming in and old flows dying out can greatly impact the amount of network coding utilized. In this paper, we propose Self-recommendation Coding-Aware Routing (SCAR), to account for these changes in network. With intermediate nodes sensing the changes, they can send self recommendations to source nodes, triggering a route-change procedure. In route-change procedure, adjustments are applied to the route metrics so that the new recommended route can be fairly weighed without bias. Simulation results show that our protocol can achieve higher throughput compared to other static coding-aware routing protocols. This is especially true in topologies where coding opportunity is scarce, or multiple-packet coding is possible. It is also shown that SCAR is more robust against changes in flow arrival sequence.