Regardless the size of a network, ODOR has a constant maximum power consumption, thanks to the optimized architecture. This coincidence is due to most packets in a network based on ODOR needs the same amount of power to route and the limited precision of the two numbers hides the small difference. A further analysis shows that the maximum power consumption of ODOR in the network is also 0.96fJ/bit. The comparison result shows that ODOR has the lowest average power consumption, 0.96fJ/bit, which is 40% less than the two crossbar architectures. The power consumption of the microresonator is expected to decrease with continual improvement of its material and internal structure. In the off- state, no power will be consumed by a microresonator, if we ignore the small bias voltages to mitigate process variations. In the on state, the microresonator need a DC current and consume less than 20μW. An optical router needs to power on and off its microresonators to route packets. (1) We assume a moderate bandwidth of 12.5Gbps for each path in the network. R is the number of routers on the i-th path.

E i is the power consumed on the i-th path when the bandwidth is B. M is the total number of paths in a network. The average power consumption E is calculated using the equation (1). To better measure the power efficiency of the optical routers, we analyzed the average power consumption of a router in the 6圆 2D mesh NoC. Due to the asymmetrical architecture of an optical router, a packet taking different input and output ports will require different amount of power to route it. Due to incomplete information, we could not compare the power consumption of λ -router with other routers. Since the -router uses WDM and a passive switching fabric, it requires extra units for wavelength selection or conversion, which the authors did not reveal the design details. We are concentrated on the second item and assume the five routers use the same networked control units and network interfaces for XY routing algorithm. Third, the networked control units of an optical NoC consume power to communicate and process routing information. Second, optical routers consume power to route packets. First, optical NoC interfaces consume power to generate, modulate, and detect optical signals. Optical NoCs consume power in three ways. For high-performance computing, low power consumption can reduce the cost related with packing, cooling solution, and system integration. Power consumption is a critical aspect of optical NoC design.

As for the ODOR architecture, the switching core only uses eight microresonators in addition to the four microresonators used by the input multiplexers for the directions. CR also requires a relative large number of microresonators because of the additional gateway accessing points to implement the 5x5 switching function. Full-connected crossbar has the second largest number of microresonators. λ -router requires the highest number of microresonators mainly due to the multistage switching structure. and optical power losses are much higher as we will see.

Longest signal path four bit or