Calibrating embedded protocols on asynchronous systems

Embedding is a method of projecting one topology into another. In one-to-one node embedding, paths in the target topology correspond to links in the original topology. A protocol running on the original topology can be modified to be executed on a target topology by means of embedding. However, if the protocol is tolerant to a number of faults - faults that affect the data but not the code of a distributed protocol executed by the nodes in a distributed systems - then the adapted protocol will not have the fault tolerance property preserved, due to the fact that links in the original topology can be embedded into paths of length greater than one: faults at the intermediate nodes on such paths are not accounted for in the protocol. We propose a communication protocol in the target topology that preserves the fault tolerance characteristics of any protocol designed for the original topology, namely by our mechanism the modification preserves fault tolerance. (C) 2009 Elsevier Inc. All rights reserved.