STorus: A new topology for optical network-on-chip

Optical Network on Chip (ONoC) architecture is emerging as a promising candidate in multiprocessor systems-on-chip (MPSoC) because of ultrahigh communication bandwidth, low latency and power consumption. The topology and layout of ONoC has a great impact on the network performance. Waveguide crossing in the topology would influence power consumption and crosstalk noise, which could influence the size of ONoC directly. In this paper, a screwy torus topology (STorus) and a new optical router are proposed. We divide an optical network into two subnets, and connect them with gateway. The diameter of STorus is half of Torus-based ONoC and almost a quarter of Mesh-based ONoC. To reduce the number of crossing, waveguide hierarchy has been employed. The simulation results show that the new topology can improve throughput by 59.1% compared with traditional mesh under hotspot traffic, and 52.3% compared with traditional mesh under uniform traffic.