Abstract: An interconnection scheme among the processing elements ("PEs") of a multiprocessor computing architecture realizes, through PE reconfiguration, both fault tolerance and a wide variety of different processing topologies including binary trees and linear systolic arrays. By using a novel variant on a tree expansion scheme, the invention also allows for arbitrary up-sizing of the PE count to build virtually any size of tree network, with each size exhibiting same high degree of fault tolerance and reconfigurability. The invention may be practiced with 4-port PEs arrayed in a module comprising a 4.times.4 board-mounted PE lattice. Each PE has four physical ports, which connect to the similar ports of its lattice neighbors. Each PE has an internal capability to be configured to route signals to or from any of its neighbors.