A new protection scheme for a combined ring-star based hybrid WDM/TDM PON architecture

In this paper we propose ahybrid WDM/TDM PON architecture that utilizes a combined ring-star based connectivity to provide shared protection against optical line terminal (OLT) failure. We have further proposed an appropriate control mechanism to reduce the protection switching time. We have evaluated the availability figures of the network service per end-user subject to different failure scenarios within the proposed network architecture along with its associated capital expenditure (CAPEX) per user. Finally we have demonstrated that our proposed architecture provides a significant cost benefit over 1:1 protection scheme for achieving almost the same value of network availability.