Packet-switched networks-on-chip (NoC) have been proposed as an efficient communication infrastructure for multi-core architectures. Adding virtual channels to a NoC helps to avoid deadlock and optimize the bandwidth of the physical channels in exchange for a more complex design of the routers. Another, possibly alternative, approach is to build multiple parallel physical networks (multiplanes) with smaller channels and simpler router organizations. We present a comparative analysis of these two approaches based on analytical models and on a comprehensive set of experimental results including both synthesized hardware implementations and system-level simulations. Categories and Subject Descriptors