Multi-Access Storage Subnetwork

摘要

The Multi-Access Storage Subnetwork is the latest addition to the Octopus Computer Network at Lawrence Livermore Laboratory. When in production in early 1978, the Subnetwork will interface a Control Data Corporation 38500 Mass Storage Facility System to the host worker computers. This will provide an on-line capacity of 1 x 10 exp 12 bits of user storage. The MASS architecture provides a very high performance approach to the management of MASS Storage, as well as a high degree of reliability needed for operation in the Laboratory's time-sharing environment. The LLL-designe subsystem combines state-of-the-art digital hardware with an innovative system philosophy. The key design features of the subnetwork which contribute to high performance include a data transmission scheme which provides a 40-megabit-per-second channel over distances of up to 1,000 feet to link MASS with the worker computer disk systems; a 280-megabit-per-second, 24-port memory multiplexor controlling a large MOS memory used for intermediate buffer between the computers and the Mass Storage; and a set of high-speed microprocessor-based controllers driving the commercial Mass Storage units. Reliability of the system is provided by a completely redundant network including two control minicomputer systems. Also enhancing reliability is error detection and correction in the MOS buffer. A 64-bit hardware-generated checksum is carried with each file throughout the entire network, insuring integrity of user files being transferred via MASS. 10 figures. (ERA citation 03:007795)