On-chip communication architecture exploration: A quantitative evaluation of point-to-point, bus, and network-on-chip approaches

Traditionally, design-space exploration for systems-on-chip (SoCs) has focused on the computational aspects of the problem at hand. However, as the number of components on a single chip and their performance continue to increase, a shift from computation-based to communication-based design becomes mandatory. As a result, the communication architecture plays a major role in the area, performance, and energy consumption of the overall system. This article presents a comprehensive evaluation of three on-chip communication architectures targeting multimedia applications. Specifically, we compare and contrast the network-on-chip (NoC) with point-to-point (P2P) and bus-based communication architectures in terms of area, performance, and energy consumption. As the main contribution, we present complete P2P, bus-, and NoC-based implementations of a real multimedia application (i. e. the MPEG-2 encoder), and provide direct measurements using an FPGA prototype and actual video clips, rather than simulation and synthetic workloads. We also support the experimental findings through a theoretical analysis. Both experimental and analysis results show that the NoC architecture scales very well in terms of area, performance, energy, and design effort, while the P2P and bus-based architectures scale poorly on all accounts except for performance and area, respectively.