[en] The system has evolved from a pair of disconnected minicomputers into a loosely coupled network of about twenty processors, ranging in power from LSI-11 microprocessors through minicomputers to a DECSystem-10 with dual KL-10 processors. The loose coupling serves to preserve the integrity and real-time performance of the online microcomputers and minicomputers, while providing a unified data structure for users from micro through mainframe. This allows FORTRAN programs to see a common data access method throughout. Considerable upgrades have been made to the system since its inception. In support of the Doublet III Vessel Modification Project (Big Dee), considerable additional enhancements are planned throughout the system of support computers, including those in the User Service Center