An adaptive routing protocol for ad-hoc networks using multiple disjoint paths

In this paper, we present the design and simulation of a source-initiated on-demand routing protocol for ad-hoc networks, which is known as the Signal-Power Adaptive Fast Rerouting (SPAFAR) protocol. SPAFAR employs efficient route discovery and maintenance mechanisms to increase bandwidth utilization and to decrease data flow disruption which occurs due to high node mobility. For the route discovery phase, we propose an algorithm to find multiple disjoint paths with longer-lived connections. This provides an efficient approach for data dispersion and for route maintenance. A longer-lived path generally involves less route maintenance. In the route maintenance phase, we propose a fast rerouting algorithm to significantly reduce data flow disruptions. Multiple paths provided by the route discovery phase significantly reduce the delay in finding an alternate path. Rerouting is proactively carried out before path unavailability occurs. A simulation study is carried out where the performance of our SPAFAR algorithm is compared with several other routing algorithms. SPAFAR exhibits a significantly better performance, due to the coupled operation of route discovery and maintenance mechanisms.