What Security Is Available for Tandem Guardian 90?
The Tandem Non-Stop system based on the Guardian 90 operating system is a unique processing environment that is different from IBM MVS and DEC VAX/VMS environments due to its fault-tolerant capabilities. This fault-tolerant operation, is accomplished through redundant hardware, backup power supplies, alternate data paths and bus paths, alternate controllers, and mirrored disks (i.e., writing data to two separate disks). The operating system contains additional functions which support the fault-tolerant capabilities. The operating system provides both multiprocessing (i.e., parallel processing in separate processors) and multiprogramming (i.e., interleaved processing in one processor). The ability to have multiple independent systems loosely coupled as one network eliminates the risk of a single point of failure. The operating system continuously checks the integrity of the system by ensuring that each of the defined processing modules are active. In the event that a processing module f
