TAMR: Traffic-Aware Multipath Routing for Fault Tolerance in 6LoWPAN

Tree based hierarchical routing is widely used in 6LoWPAN due to advantages of low control overhead and low memory resources. However, it generates a triangular detour path considering point-to-point (P2P) traffic. Reactive routing provides a reasonable P2P path by conducting flooding-based route discovery, but the flooding increases packet interference due to huge control overhead. Multipath routing can improve the reliability by preparing for the alternative path. Nevertheless, it needs an extra table for storing the alternative path and it is not appropriate to diverse traffic patterns. In this paper, we propose a traffic-aware multipath routing (TAMR). By managing an overlaid topology comprised of two different topologies without additional overhead, TAMR can dynamically choose a proper routing protocol according to traffic patterns and it can improve network reliability. Besides, TAMR is suitable for 6LoWPAN, because it does not need to store global routing state and generates low control overhead. In order to evaluate the performance, we have conducted the simulation by comparing with representative routing protocols in 6LoWPAN. The results show the overall performance of TAMR surpasses others in terms of hop count, packet delivery ratio, number of control packets, and memory usage.