Soft-failure Identification and Localization Method Based on Received Optical Signal Quality and Repeater Nodes’ Performance

We propose novel methodology to identify and localize soft-failures using performance metrics monitored at repeater nodes in addition to signal quality monitored at transponders and show feasibility in experiments using commercial equipment and field-deployed fibers.

1. Introduction

Optical transport networks require high availability since they are important infrastructure that accommodates various communication services. Although service disruptions can be prevented owing to their redundancy such as path protection, failed equipment has to be repaired quickly to recover networks’ redundancy.