Survivable green active topology design and link weight assignment for IP networks with NotVia fast failure reroute

Survivability and energy efficiency are in conflict with each other on network resources usage in IP networks. The basic principle to achieve high survivability is via provisioning backup paths over spare capacity. However, in designing an energy efficient network, the target is the opposite. In order to minimize energy consumption, routing and traffic engineering techniques are applied to aggregate flows so as to minimize network resource usage. The unused network devices are turned off for power saving. How to reduce power consumption while maintaining high survivability is quite a challenging task. In this paper, we first evaluate the survivability for an IP network using various IP fast reroute (IPFRR) schemes. The results indicate that NotVia IPFRR is one of the most suitable schemes for designing a survivable green IP network. Therefore, in this work, we focus on studying the active topology design and link weight assignment problem for energy efficient IP networks with NotVia IPFRR. We have formulated the problem as an integer linear programming problem and propose a Lagrangean relaxation-based approach to obtain a near optimal solution. The numerical results indicate that the proposed method is not only energy efficient but also has a 100% network survivability capability against any single node failure.