14 - UCA protocol

Abstract

The chapter describes the overall structure of the Utilities Communication Architecture (UCA) protocol and the uniform application interface. UCA is intended to allow utilities to purchase “off-the-shelf” UCA-compliant devices—such as pole top reclosures, transformers, pumps, valves, and flow meters—and to have these devices automatically integrated into the supervisory control and data acquisition (SCADA) and information technology systems. The three basic building blocks of the UCA are uniform communications infrastructure, uniform data model, and uniform application interface. The UCA categorizes their profile stack as the L, T, and A Profiles. The L-Profile corresponds to the open systems interconnection (OSI) physical and data link layers. The T-Profile corresponds to the OSI network and transport layers. The A-Profile corresponds to the OSI session, presentation, and application layers. The UCA uses the manufacturing message specification (MMS) standard. MMS provides the message structure, message syntax, and message dialog procedures for monitoring and controlling information communications. The uniform applications interface consists of common applications services model, UCA data acquisition and control (DAC) client, UCA data repository, and UCA DAC server.