Optical-Layer Restoration in a Self-Healing Ring Network Using a Wavelength-Blocker-based Reconfigurable Optical Add/Drop Multiplexer

Optical-layer restoration has been demonstrated with a wavelength-blocker (WB)-based reconfigurable optical add/drop multiplexer (ROADM). Two 2 x 2 optical switches with a control circuit were placed before and after a WB-based ROADM to provide automatic path restoration under fiber-failure conditions. Using the proposed node configuration, a 3-node self-healing ring (SHR) network has been implemented to demonstrate the feasibility of the automatic optical-layer restoration. From the results, the restoration time was measured to be similar to 4 ms under fiber-failure conditions, without any additional power penalty in receiver sensitivity.