The fault-tolerant 3B-20 processor
L. E. Gallaher, Wing N. Toy · 1981
The 3B-20 is the first Bell System general-purpose telecommunication processor designed to meet a broad range of applications. New features such as memory management are incorporated into its design to support a modern operating system. Hardware supports are provided to efficiently execute a high-level language. The 3B-20 Processor is designed to meet ESS reliability requirements and the proven technique of self-checking duplex operation forms its basic architecture structure.