A Hybrid Ring/Mesh Interconnect for Network-on-Chip Using Hierarchical Rings for Global Routing

A popular network topology for network-on-chip (NoC) implementations is the two-dimensional mesh. A disadvantage of the mesh topology is in its large communication radius. By partitioning a two-dimensional mesh into several sub-meshes and connecting them using a global interconnect, we can reduce the average number of hops for global traffic. This paper presents a hybrid architecture that partitions a large 2D-mesh into several smaller sub-meshes which are globally connected using a hierarchical ring interconnect. Hierarchical rings have been selected for study because of their simplicity, speed and efficiency in embedding onto a circuit layout, as well as for their suitability for efficient cache coherent protocols. An original SystemC modeling platform was implemented in order to compare the traditional 2D-mesh with the hybrid ring architectures and the simulation results will show that our hybrid architecture does indeed have a positive effect on the average hop count