Surviving link failures in multicast VN embedded applications

Abstract

Virtual network embedding (VNE) is defined as the allocation of network resources to multiple virtual networks (VNs) and is recognized to be a challenging task to perform efficiently. Virtual network survivability is a new term that describes the measures taken to provide a failure-proof VN against physical link and/or node failure. Indeed, a single link or node failure in a substrate network can bring down multiple hosted VNs, i.e., the ones that utilize that failed link or node. As such, virtual network survivability becomes an essential part of VNE. While much work has been dedicated to studying the impact of a variety of failure cases in a VN, little attention has been directed towards studying the link failure impact on multicast virtual network (MVN) applications, which principally restrict end-to-end delay and delay variation measures. In fact, most of the introduced survivability schemes adopt protection techniques by reserving backup resources prior to embedding, which inevitably leads to under-utilization of the network resources. In this paper, we first investigate the impact of physical link failure on MVNs. Then, we introduce a novel recovery approach to restore MVNs while considering their end-delay and delay variation requirements. Simulation experiments prove that our recovery technique achieves good restoration ratio in considerably fast execution time and low link mapping cost with little impact on the admittance ratio.