XYX: A Power & Performance Efficient Fault-Tolerant Routing Algorithm for Network on Chip

Reliability is one of the main concerns in the design of network on chips due to the use of deep-sub micron technologies in fabrication of such products. This paper proposes a fault-tolerant routing algorithm called XYX which is based on sending redundant packets through the paths with lower traffic loads. The XYX routing algorithm makes a redundant copy of each packet at the source node and exploits two different routing algorithms to route the original and the redundant packets. Since two copies of each packet reach the destination node, the erroneous packet is detected and replaced with the correct one. Due to the use of paths with lower traffic rates for sending redundant packets and minimizing the number of sent redundant packets, the XYX routing algorithm provides lower performance and power overheads as compared to flood-based routing algorithms. Experimental results show that the XYX routing algorithm imposes negligible performance and power consumption overheads while providing almost the same reliability in comparison with flood-based routing algorithms.