Dimensioning networks of ROADM cluster nodes

Abstract

Next-generation optical networks require high-degree, high-capacity reconfigurable optical add-drop multiplexer (ROADM) nodes and intelligent network planning schemes. We propose a cluster ROADM node design and a network dimensioning method that optimizes the resource utilization of optical networks with cluster nodes. The proposed ROADM cluster node offers a flexible add-drop rate, scaling to 100s of degrees, and a cost per degree similar to today’s ROADM. It disaggregates the cluster’s line and add-drop functions into different chassis. The low-cost node architecture is complemented by an order-based connection management algorithm that achieves better than 10−4 blocking despite being equipped with less than 30% dilation in the cluster design. For an optical network with ROADM cluster nodes, we propose a network dimensioning scheme that proactively uses network knowledge to determine the optimum degree for ROADM nodes as demand increases. The results show a much-improved blocking rate, particularly at medium to high loading and an average of 3.1% increased utilization on each network’s fiber compared with reactive schemes.