Reliable communication in cube-based multicomputers using safety vectors

Reliable communication in cube-based multicomputers (including disconnected ones) using the safety vector concept is studied in this paper. In the proposed approach each node in a cube-based multicomputer of dimension n is associated with a safety vector of n binary numbers which is an approximated measure of the number and distribution of faults in the neighborhood. The safety vector of each node in an n-dimensional hypercube can be easily calculated through n-1 rounds of information exchange among neighboring nodes. Optimal unicasting between two nodes is guaranteed if the kth bit of the safety vector of the source node is one, where k is the Hamming distance between the source and the destination. An extended deadlock-free unicasting using virtual channels is also introduced.