Depth-First Forwarding for Unreliable Networks: Extensions and Applications

摘要

This paper introduces extensions and applications of depth-first forwarding (DFF)—a data forwarding mechanism for use in unreliable networks such as sensor networks and Mobile NETworks with limited computational power and storage, low-capacity channels, device mobility, etc. Routing protocols for these networks try to balance conflicting requirements of being reactive to topology and channel variation while also being frugal in resource requirements—but when the underlying topology changes, routing protocols require time to re converge, during which data delivery failure may occur. DFF was developed to alleviate this situation: it reacts rapidly to local data delivery failures and attempts to successfully deliver data while giving a routing protocol time to recover from such a failure. An extension of DFF, denoted as DFF++, is proposed in this paper, in order to optimize the performance of DFF by way of introducing a more efficient search ordering. This paper also studies the applicability of DFF to three major routing protocols for the Internet of Things (IoT), including the Lightweight On-demand Distance-vector Routing Protocol—Next Generation (LOADng), the optimized link state routing protocol version 2 (OLSRv2), and the IPv6 routing protocol for low-power and lossy networks (RPL), and presents the performance of these protocols, with and without DFF, in lossy and unreliable networks.