Optimally Selecting Standby Virtual Routers for Node Failures in a Virtual Network Environment
Xuan Liu, Deep Medhi · IEEE Transactions on Network and Service Management · 2017
In a virtual network environment, a substrate network provider allocates computing and networking resources for service providers who request virtual networks to be created for particular services, and it also has the capability to provide resilient virtual network management with redundant resources, such as dynamic virtual network restoration from failures. In this papers, we consider the situation where the substrate network provider desires to have standby virtual routers ready to serve virtual networks under node failures. Such a failure can affect one or more virtual routers in multiple virtual networks. The goal of this paper is to make the optimal selection of standby virtual routers so that virtual networks can be dynamically reconfigured back to their original topologies right after the failures. We present an optimization formulation and a heuristic for this problem. By considering a number of factors, we present numerical studies to show how the optimal selection was affected by those factors, and the proposed heuristic's performance was close to the optimization model when there were sufficient standby virtual routers for each virtual network and the substrate nodes have the capability to support multiple standby virtual routers to be in service concurrently.