A Network-on-Chip router for deadlock-free multicast mesh routing

This paper presents a novel method to deal with deadlocking in multicast routing in mesh Network-on-Chip. The proposed design does not use the virtual channels used in the conventional designs, instead it provides a unique method to interleave data from different input ports. The method avoids deadlocking in tree-based multicasting by providing a flit-by-flit interleaving and at the same time reducing the Head-of-Line blocking. Therefore, the design reduces the latency while routing to multiple destinations, thereby improving over the limitation offered by most of the multicast deadlock avoidance techniques. The effectiveness of the proposed routing design has been verified by subjecting the router to different traffic congestions. It has been observed that the present design could reduce the latency by nearly half, as compared to the conventional combined method of wormhole and flit level virtual cut-through switching.