Cost- and energy-efficient filterless architectures for metropolitan networks

Network operators are forced to find cost- and energy-efficient solutions for networks supporting new and emerging services with strict latency and ultra-high-capacity requirements. A disruptive approach for delivering network agility in a cost- and energy-efficient manner is employing filterless optical networking based on broadcast-and-select nodes and coherent transceivers. The filterless network concept has been widely studied for terrestrial and submarine applications. In this paper, we investigate the performance of filterless optical networks in metropolitan core and aggregation networks where agility is required due to service dynamics, customer changes, and service flexibility requirements. We compare our results with a conventional metro network based on active switching. The results show that the filterless metro network based on a hierarchical structure similar to its active switching counterpart has comparable installed first cost and spectrum usage at 11 Tb/s of total traffic, as well as cost and wavelength consumption advantages of 19.5% and 16%, respectively, at 107 Tb/s of total traffic. These results confirm that the filterless architecture is an attractive alternative for metro network deployments.