Investigation of fast reroute mechanisms in an optical testbed environment

Abstract

In this paper, we investigate and evaluate the performance of two fast reroute mechanisms in packet switched core networks. Such mechanisms enable, in the case of a network fault, the fast switchover of protected traffic onto pre-established backup paths within minimal time (typically below 50 ms) to minimize traffic loss. Our research testbed consists of both real and emulated IP/MPLS Label Switching Routers (LSRs). Using empirical tests, we compare the two fast protection mechanisms MPLS Traffic Engineering (TE) Fast Reroute (FRR), and IP FRR to protect MPLS LDP traffic. In our tests, we consider single link failures protected with pre-provisioned backup paths using TE-FRR tunnels, or IP Fast Reroute (IP-FRR) alternate paths. We compare the two techniques in terms of traffic loss and network time convergence obtained by repeating the tests multiple times.