Robust on-demand multipath routing with dynamic path upgrade for delay-sensitive data over Ad Hoc networks

Node mobility in mobile ad hoc networks (manets) causes frequent route breakages and intermittent link stability. in this paper,we introduce a robust routing scheme,known as ad hoc on-demand multipath distance vector with dynamic path update (aomdv-dpu),for delay-sensitive data transmission over manet. the proposed scheme improves the aomdv scheme by incorporating the following features: (i) a routing metric based on the combination of minimum hops and received signal strength indicator (rssi) for discovery of reliable routes; (ii) a local path update mechanism which strengthens the route,reduces the route breakage frequency,and increases the route longevity; (iii) a keep alive mechanism for secondary route maintenance which enables smooth switching between routes and reduces the route discovery frequency; (iv) a packet salvaging scheme to improve packet delivery in the event of a route breakage; and (v) low hello packet overhead. the simulations are carried out in ns-2 for varying node speeds,number of sources,and traffic load conditions. our aomdv-dpu scheme achieves significantly higher throughput,lower delay,routing overhead,and route discovery frequency and latency compared to aomdv. for h.264 compressed video traffic,aomdv-dpu scheme achieves 3 db or higher psnr gain over aomdv at both low and high node speeds. © 2013 sunil kumar et al.