Ring-based local access PON architecture for supporting private networking capability

Abstract

We propose what we believe is a novel ring-based local access Passive Optical Network (PON) architecture that addresses some of the limitations of current tree-based PON architectures including supporting private networking capability. Specifically, we propose and devise a simple ring-based Ethernet PON (EPON) architecture that supports a truly shared LAN capability among end users as well as upstream access to the central office. Unlike a typical ring-based PON topology in which the optical line terminal (OLT) and the optical network units (ONUs) are interconnected via a long fiber ring, under the proposed architecture, ONUs are interconnected via a short distribution fiber ring in the local loop but share the standard trunk feeder fiber for long reach connectivity to the Central Office (CO). The main characteristic of the proposed architecture is that it supports a fully distributed control plane among the ONUs for ONU-ONU communication as well as upstream access to the OLT. This architecture is well suited for an autonomous access environment such as a university campus or a private corporation where several buildings are closely dispersed within a 0.5-1 km diameter area.