A Survey of Emerging Interconnects for On-Chip Efficient Multicast and Broadcast in Many-Cores

Networks-on-chip (NoC) have emerged to tackle different on-chip communication challenges and can satisfy different demands in terms of performance, cost and reliability. Currently, interconnects based on metal are reaching performance limits given relentless technology scaling. In particular, a performance bottleneck has emerged due to the demands for communication in terms of bandwidth for multicasting and broadcasting. As a result, various state-of-the-art architectures have been proposed as alternatives and emerging interconnects including the use of optics or radio frequency (RF). This article presents a comprehensive survey of these various interconnect fabrics, and discusses their current and future potentials and obstacles as well. This article aims to drive the research community to achieve a better utilization of the merits of on-chip interconnects and addresses the challenges involved. New interconnect technologies, such as optical interconnect, wireless NoC (WiNoC), RF transmission lines (RF-I) and surface wave interconnects (SWI), are discussed, evaluated and compared. Consequently, these emerging interconnects can continue to provide the cost efficiency and performance that are highly demanded for future many-core processors and high performance computing.