An overlaid switching network is derived by overlaying perpendicularly one multistage interconnection network with a second multistage interconnection network. The new network is formed by placing a switching element corresponding to the position of switching elements in either multistage interconnection network. Each switching element in the overlaid network has the ports defined by the two multistage interconnection networks as does its interconnection networks. A special case occurs when the number of rows and columns of the first multistage interconnection network is the number of columns and rows of the second multistage interconnection network, respectively. The overlaid switching networks also inherit their upgradeability from the multistage interconnection networks from which they are derived, such as in the case of a redundant blocking compensated cyclic group multistage network.