A large-scale distributed control system on multi-vendor platform

Two large-scale distributed control systems using general-purpose UNIX(TM) computers and conforming to the Single UNIX Specifications (SUS) as the first stage have been applied to local control systems which supervise regional power network in Tokyo Electric Power Company. HP-UX(TM) operating system is used for the first and the second system; simultaneously, the applications on Solaris(TM) have been verified from functions and their performance points of view. Based on the results of verification, a decision was made to introduce Sun's computers for the third system to be put into practical use since March 2002. This paper describes technological issues and solutions for multi-vendor platform which ensures the portability of applications. The main three issues addressed herein are: (1) the middleware that handles the differences of operating system (OS) implementations and (2) system performance assessment technology for the different computers. For a longer system life by partial replacement of computers in a multi-vendor system, (3) system behaviors and performance on comprising configuration with different computers (vendors, computers and/or operating system) are also discussed. By solving the issues, the middleware as a multi-vendor platform and portable applications can be built.