Parallel implementation of the algebraic path problem

Abstract

The Algebraic Path Problem is a general framework which unifies several algorithms arising from various fields of computer science. Rote [11] introduces a general algorithm to solve any instance of the APP, as well as a hexagonal systolic array of (n+1)2 elementary processors which can solve the problem in 7n-2 time steps. We propose a new algorithm to solve the APP, and demonstrate its equivalence with Rote's algorithm. The new algorithm is more suitable to parallelization: we propose an orthogonal systolic array of n(n+1) processors which solves the APP within only 5n-2 steps. Finally, we give some experiments on the implementation of our new algorithm in the parallel environment developped by IBM at ECSEC in Roma.