Data Highway Systems-Report

Publisher Summary This chapter presents a discussion on the different aspects of data highway systems. Mr. Wood opened the discussion with an outline of the data highway requirements in a process plant. These requirements were identified using PROWAY as a reference definition. Mr. Wood identified several issues that need resolution, and invited the panel members to give presentations about these questions, seeking to identify the issues and start discussion. Mr. Janetzky introduced two main alternative architectures for discussion: (1) a single highway structure; and (2) a local bus concept using networking features to interconnect different independent buses. The audience saw a need for both approaches and asked how the work of PROWAY meets the local bus need with multiple buses and networking. It was explained that PROWAY sees this as future work once the single bus has been standardized. Dr. Becker described an example of optical highway communication using double ring connections among a number of control stations in an industrial plant. Optical fiber connections with present technology constrain the user to install point-to-point connections with store and forward between segments of a highway. I