Extensible optical access network enabling multistage protections and data aggregation based on tangent rings

In this paper, an extensible optical access network architecture is proposed on the basis of multiple tangent single-fiber rings. With the proposed architecture, both multistage protections and data aggregation can be realized. Optical line terminal and remote nodes RNs can automatically switch to protection mode to overcome fiber failure occurring in both main ring MR and sub-rings SRs. The RNs, which are designed as tangent points, can realize wavelengths adding and dropping between MR and SRs, and they also can realize the network expansion conveniently and smoothly through adding more wavelengths. So, it is a good selection for next-generation large-scale access networks. Copyright © 2013 John Wiley & Sons, Ltd.