Incorporating multicast traffic grooming routing and spectrum assignment in flex-grid optical network using sub-light tree sharing approach

Abstract

Flex-grid optical networks based on orthogonal frequency division multiplexing support quite high bit rates (beyond 400 Gb/s). The flexible grid and elastic bandwidth allocation scheme of flex-grid optical networks are suitable for transmitting growing internet traffic. Multicast applications can be routed using a tree structure connecting a source to its destinations. All optical multicasting using light-tree concept, eliminates the use of electrical-optical-electrical conversion at intermediate nodes. In our proposed approach, we consider grooming multicast requests in flex-grid optical network (also called elastic optical networks). The nodes are multicast-capable and there is no spectrum conversion. The aim is to satisfy all multicast requests along with reduced network cost. Network cost can be minimized by reduced spectrum requirement and reduced number of splitters required. Here we consider same-source grooming and study two types of grooming; light tree sharing by fully matching multicast requests and sub-light tree sharing by partially matching multicast requests. The simulation results show considerable amount of spectrum saving and reduced splitter count for grooming approach compared to existing non-grooming approach.