Deployment of survivable fiber-wireless access for converged optical and data center networks

As a promising solution for the bandwidth bottleneck of Data Center (DC) network, the converged optical and DC networks have gained an increasing popularity due to their advantages in rich bandwidth and high reliability. Although the converged optical and DC networks bring the opportunity for high-speed transmission of DC traffic, they also impose more severe challenge on the survivability design, because the network component failure will cause greater data loss. Some works focus on the survivability of core network for the convergence of optical and DC networks and remain less touched on that of access network. In fact, access network plays an important role in the reliable transmission of the traffic between end-users and DC, which accounts for considerable portion of all DC traffic. However, since the vulnerability to component failure, the traditional Passive Optical Network (PON) may no longer satisfy the higher survivability requirement. As an emerging broadband access technology, Fiber-Wireless (FiWi) may be a preferable candidate for the survivable access of converged optical and DC networks. In FiWi access network, the Wireless Mesh Network (WMN) at front-end can protect the Passive Optical Network (PON) at back-end by wirelessly rerouting. This paper focuses on the deployment of survivable FiWi access network against single distribution fiber failure, which is a typical failure scenario in optical access network. We propose a new protection approach called Wireless Rerouting with Backup Radios (WRBR) for the deployment of survivable FiWi access network. In WRBR, we deal with the optimization of wireless routers placement and backup radios configuration. Both Integer Linear Programming (ILP) and heuristic approach are proposed, aiming to minimize the deployment cost. Simulation results demonstrate the advantage of WRBR in saving deployment cost of FiWi access for converged optical and DC networks over the previous works.