Reliable communications in optical network-on-chip by use of fault tolerance approaches

We present schemes for reliable communications in Optical Networks on Chip (ONoC) through employing information redundancy and hardware redundancy. By means of optical parity generators, SNR associated errors can be detected at the destinations. Besides SNR-based faults, thermal sensitivity of micro ring resonators can be a threat to the communications reliability. Thermal stabilization methods because of consuming large portion of the on-chip power, directly affect the power efficiency of the optical NoC. Hence, in this paper, using redundant rings which perform in different thermal variations is proposed to reduce the thermal variations-based errors. Simulation results demonstrate that using parity generators in the photonic layer although imposing higher energy consumption to this plane, it reduces the latency overhead about 16% in compared with their electrical counterpart. Moreover, redundancy technique can achieve 20% improvement in power consumption with negligible area overhead.