Testing the Functional Requirements of the Switch Interface Unit

Abstract

Isotach networks provide special guarantees about message ordering and delivery times in a parallel or distributed computing environment. Although isotach networks can be implemented entirely in software running on commercial off-the-shelf hardware, an isotach network that uses custom hardware to maintain logical time may be particularly efficient. A hardware-based implementation of an isotach network has been designed and built using custom components, one of which is the switch interface unit (SIU). An SIU handles isotach functions for a host. These functions include the maintenance of logical time, the timestamping of outgoing isotach mesages, and the exchange of tokens with another custom hardware device,the token manager. We have designed and performed tests to analyze the switch interface units and increase confidence that the SIUs are functioning correctly. The analysis has indicated that the new units are working properly.