Near loop-free routing: increasing path choices with stateful forwarding

Abstract

When splitting traffic for one destination among multiple paths, the employed paths should be loop-free, lest they waste network resources, and the involved routers should be given a high path choice, that is, a high number of potential nexthops. In IP networks this requires the use of a loop-free routing protocol, which limits the achievable path choice. Here we show that, in NDN, we can increase the path choice by combining a Near Loop-free Routing protocol (NLR) with on-demand loop removal at the forwarding layer. NLR routers 1) exclude the incoming face from forwarding, 2) use certain heuristics to minimize routing loops, and 3) remove any remaining loops at the forwarding plane. NLR achieves a higher path choice and path quality than current alternatives, while keeping computation complexity low.