The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 14, 2009
Filed:
Dec. 20, 2005
Fumitoshi Mizutani, Tokyo, JP;
Fumitoshi Mizutani, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
There is provided a fault tolerant system capable of adequately performing error processing, synchronization processing, and resynchronization processing for realizing a fault tolerant function in accordance with the system state. The fault tolerant system comprises at least two systems including: a CPU subsystem; an IO subsystem connected to the CPU subsystem; an FT controller to be connected between the CPU subsystem and IO subsystem; and crosslinks connecting own system and other system through the FT controller. The CPU subsystem operates at the same timing with a CPU subsystem of other system in lock-step. The FT controller manages a plurality of system operations, according to which both systems perform error processing, duplication processing, and resynchronization processing for fault tolerant, by associating a plurality of states corresponding to the system operations with predetermined event signals. According to these event signals, the FT controller selects the system operations while changing the states for every system and allows the CPU subsystem to perform the selected system operation.