Fault-Tolerance Ring Network on Chip without Buffer

The paper brings forward a hierarchical ring NoC (Network on Chip) topology whose links are divided into two groups of rings for fault-tolerance. Each group of ring contains one control-ring and one data ring. Control-ring propagates the information of routing, link error and error control of all nodes using packet switching. Data-ring exchanges data using circuit switching. Three pipeline stages architecture without buffer is presented that minimizes the delay of communications among nodes. Ring network adopts time division multiplexing and priority mechanism to implement space division multiplexing of bandwidth and fair routing. Simulation results show that the architecture can efficiently avoid traffic congestion, deadlock and starvation and ensure full use of bandwidth.