05802265 is referenced by 31 patents and cites 13 patents.

In a fault-tolerant computer system, a primary replica supervisor is interposed between an operating system and a primary replica of an application program being executed by a primary processor. An object-code editor locates calls to the operating system and loops in the application program and inserts instruction sequences that enable the replica supervisor to intercept the calls to the operating system, results returned by the operating system as a result of the calls and asynchronous events delivered by the operating system to the replica. A backup replica supervisor is similarly interposed between an operating system and a backup replica of the application program being executed by a backup processor. The primary replica interacts with an environment. The replica supervisors ensure that the backup replica undergoes state transformations, as a result of the calls to the operating system and asynchronous events, that are equivalent to state transformations that the primary replica undergoes as a result of corresponding calls and asynchronous events. Thus, after a failure in the primary processor, the backup replica can interact with the environment in a manner consistent with interactions between the primary replica and the environment prior to the failure.

Title
Transparent fault tolerant computer system
Application Number
8/565145
Publication Number
5802265
Application Date
December 1, 1995
Publication Date
September 1, 1998
Inventor
John D Service
Chelmsford
MA, US
Fred B Schneider
Ithaca
NY, US
Bradford B Glade
Harvard
MA, US
Robert C B Cooper
Wellesley
MA, US
Kenneth P Birman
Ithaca
NY, US
John E Ahern
Sudbury
MA, US
Thomas C Bressoud
Northborough
MA, US
Agent
Cesari and McKenna
Assignee
Stratus Computer
MA, US
IPC
G06F 11/34
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