Assessing the energy break-even point between an optical NoC architecture and an aggressive electronic baseline

Many crossbenchmarking results reported in the open literature raise optimistic expectations on the use of optical networks-on-chip (ONoCs) for high-performance and low-power on-chip communication. However, most of those previous works ultimately fail to make a compelling case for chip-level nanophotonic NoCs, especially for the lack of aggressive electronic baselines (ENoC), and the poor accuracy in physical- and architecture-layer analysis of the ONoC. This paper aims at providing the guidelines and minimum requirements so that nanophotonic emerging technology may become of practical relevance. The key differentiating factor of this work consists of contrasting ONoC solutions with an aggressive ENoC architecture with realistic complexity, performance, and power figures, synthesized on an industrial 40nm low-power technology. At the same time, key physical design issues and network interface architecture requirements for the ONoC under test are carefully assessed, thus paving the way for a well-grounded definition of the requirements for the emerging ONoC technology to achieve the energy break-even point with respect to pure electronic interconnect solutions in future multi- and many-core systems.