Distributed communications

Communications among multiple Ada programs is a must, either as an explicit link or as an invisible link hidden beneath a distributed Ada veneer. Unisys has defined two Ada package specifications for inter-program communications, that are derived from the requirements developed at the Third International Workshop on Real-Time Ada Issues (RTAW3). Unisys is implementing these packages on several embedded real-time testbeds, both as standalone capabilities for application developers and as the communication layer supporting a distributed Ada system. These specifications are proposed as a basis for a secondary standard for inter-program communication for Ada9X.

This paper describes how these specifications match the RTAW3 requirements and the motivation for their features. Some details of the specifications are interspersed throughout the text, with a full specification contained in the appendix.