TR2012-060

Loop-Free Routing in Low-Power and Lossy Networks



IPv6 based Low-Power and Lossy Networks (LLNs) are emerging. Internet Engineering Task Force (IETF) has developed an IPv6 Routing Protocol for LLNs (RPL), which is widely considered as a feasible routing protocol for LLNs. However, routing loops and lack of a loop-free local route repair mechanism are two major open issues to be addressed in RPL. Based on the framework of RPL, this paper proposes a Loop-Free Routing Protocol for LLNs (LRPL). We provide an innovative rank computation method and a loop-free local route repair mechanism to eliminate routing loops in RPL. Simulation results show that the proposed LRPL performs much better than conventional routing protocols in terms of packet delivery rate, end-to-end packet delay, and routing overhead.