  Aspects of compatibility of topologies of parallel computing systems and
tasks are investigated. The introduction of appropriate indexes based on the
original topological model of parallel computations and on the nontraditional
description of a graph by its projections is proposed and elucidated. On the
example of hypercubic computing system (CS) and tasks with ring and star
information topologies, we demonstrate determining the indexes and their use in
a comparative analysis of the applicability of interconnect with a given
topology for solving tasks with the same and different types of information
topologies.
