Load balanced optical network unit (ONU) placement in cost-efficient fiber-wireless (FiWi) access network

Fiber-wireless (FiWi) access network is a promising access technology because it integrates the merits of optical and wireless access networks. In FiWi network, the placement of optical network units (ONUs) is one of the key issues for the network deployment since the ONU acts as the interface between wireless front-end and optical back-end. Some works have been carried out to investigate the ONU placement in FiWi. However, most of these works consider only the Internet traffic and ignore the effect of peer-to-peer (P2P) traffic on the ONU placement. Furthermore, all of these works remain untouched on the issue of load balancing among different ONUs. In this paper, we propose a novel ONU placement algorithm called load balanced ONU placement (LBOP) with the consideration of both Internet traffic and P2P traffic. According to the LBOP algorithm, with the objective of minimizing the number of ONUs, we first place the ONUs one-by-one in a greedy manner under the constraints of wireless hop number for both types of traffic. Then, for the purpose of load balancing, we implement the load transferring among different ONUs by coordinating the sets of their subordinate wireless routers. Simulation results demonstrate that the proposed LBOP algorithm is more effective in reducing the number of ONUs and achieving the load balancing than previous works. (C) 2013 Elsevier GmbH. All rights reserved.