Metacube – A New Interconnection Network for Large Scale Parallel Systems

The hypercube has been widely used as the interconnection network for parallel computers. However, in hypercubes, the number of communication links for each node is a logarithmic function of the total number of nodes. Therefore, the hypercube is not a good candidate for an interconnection network for a very large parallel computer that might contain hundreds of thousands of nodes due to IC technology and port number limitations. This paper introduces a new interconnection network for very large parallel computers called metacube (MC). An MC network has a 2-level cube structure. An MC(k,m) network can connect 2m2 +k nodes with m+k links per node, where k is the dimension of the high-level cubes (classes) and m is the dimension of the low-level cubes (clusters). An MC network is a symmetric network with short diameter, easy and efficient routing and broadcasting similar to that of the hypercube. However, an MC network can connect millions of nodes with up to 6 links per node. An MC(2,3) with 5 links per node has 16,384 nodes and an MC(3,3) with 6 links per node has 134,217,728 nodes. We describe the MC network’s structure, topological properties and routing and broadcasting algorithms.