Congestion Aware Negative First Routing with Fair Arbitration for Network on Chip

Advancements in sub micron technology have increased the quantity of Intellectual Properties (IPs) embedded onto the System-on-Chip (SoC), which enabled multi-core SoCs. The conventional inter connection used in these SoCs lead to a complex system with traverse delays. In SoCs, Network on Chip (NoC) removes the difficulties encountered with the conventional inter connections and provides an efficient transfer of data between the cores. In NoC, there is an additional requirement of routing algorithms that paves way for least paths and avoids the path based on congestion as well. We propose a Congestion Aware Negative First routing algorithm with Fair Arbitration (CANF-FA) in this paper which depends on the Negative-First (NF) turn model that issues adaptability and is free of deadlock, for a 2D NoC connected using mesh topology. The algorithm proposed is implemented with the help of a cycle accurate simulator and analyzed on various patterns of traffic namely – Transpose-1, Random, Bit-Reversal and Transpose-2. Considering all the above mentioned patterns of traffic, the results of the simulation are compared with the preceding algorithm. The proposed routing algorithm displays a good amount of drop in latency and a considerable increase in the throughput of packets for all the mentioned patterns of patterns.