A Novel Design of Cost-Efficient Long-Reach Survivable Wireless-Optical Broadband Access Network

Abstract

Wireless-optical broadband access networks (WOBANs) have gained extreme importance due to their ability to provide ubiquitous and high-speed Internet access. Since in long-reach WOBAN, wireless front-end is fed by a long-reach optical back-end, provisioning protection against failure of a WOBAN segment (due to failure of its feeder fiber and/or optical line terminal) is a primary concern. The failure causes simultaneous disconnection of a large number of users, resulting to poor connection availability and service dissatisfaction for users and high revenue loss for network operators. Focusing on the problem of a WOBAN segment failure, we propose a novel multi-cast multi-hop protection architecture (MCMHPA) to design a survivable WOBAN wherein traffic of a failed WOBAN segment is recovered by employing the residual bandwidth of other neighboring WOBAN segments. In MCMHPA, we provide a novel architecture of backup optical network units (optical devices used to transmit/receive traffic in condition of the segment failure) to implement multi-cast and multi-hop mechanisms. The proposed architecture offers multi-hop backup optical paths by using the minimum number of optical devices and fibers, thereby incurring low expenditure to design a survivable WOBAN.