RSFR: A Recursive Self-Testable and Fault-Tolerant Routing Protocol for NoC Routers

This paper proposes a novel routing algorithm and test strategy which provides deadlock freedom, low packet dropping and low latency in networks-on-chip (NoCs).We first propose an algorithm, in which functionality of a router is revised in order to enable it to test its own, as well as the preceding router s, functionality. The recognized faults are reported to successive routers along the packet s path to the destination without the need for generating any extra non-data packet. Furthermore, we enrich the initial scheme by adding several features such as ability to backtrack the misled packets, prediction of the safest path to destination, and clearance of transient faults. We show that the enriched approach, namely RSFR, demonstrates a significant performance improvement in terms of latency, drop-rate and fault coverage while retaining deadlock-freedom. The experimental results illustrate that fault coverage for routers can reach up to almost 100% with yet low power consumption.