A NOVEL FAULT TOLERANT SWITCH FOR RELIABLE NoC DESIGN

Abstract

Network on chip (NoC) is a design space covered by the manifold combinations of network topology options, routing algorithms, switch architectures, fault tolerant mechanisms and so on. In NoC structures, switches and links are important components on network layers and the effect of faults on links and switches in NoC leads to disturbance in internal communication and low reliability. The performance reduction of many-core NoC architectures depend strongly on the number of faulty switches. This bottleneck motivates us to propose a fault tolerant switch in which the ring roads help the switch to tolerate the faulty ports and also faulty cores. In the proposed scheme, switch ports are connected via redundant ring roads and so the connection with adjacent nodes is not limited to one port. Moreover, if the switch core is defected, the node stays active and cooperates in packet forwarding process. The main advantages of the proposed scheme are tolerating the permanent faults on core and ports of a switch and handling the input traffic of a faulty switch by preventing the congestion around the faulty region. The simulation results verify the robustness of the proposed intelligent switch against various kinds of permanent faults in NoC architectures.