Coverings that preserve sense of direction
Sense of direction is a property of labelled networks (i.e., are-coloured graphs) that allows one to assign coherently local identifiers to other processors on the basis of the route followed by incoming messages. We prove that (weak) sense of direction is preserved by the construction of regular coverings (i.e., coverings induced by voltage assignments in a group) whose voltage assignment depends only on colours. Moreover, this construction preserves minimality. (C) 2000 Elsevier Science B.V. All rights reserved.
sense of direction distributed systems interconnection networks graph coverings