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:
Aug. 06, 1996
Filed:
Mar. 25, 1994
Wayne C Carlson, Tucson, AZ (US);
Michael J Meadows, Tucson, AZ (US);
Merrill B Greco, Tucson, AZ (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
The present invention provides a method and apparatus for reducing the overhead required in conventional fault tolerant processing by redundant processors. Commands are received and queued by both the active and standby units but are processed only by the active unit. Short messages, each including a command identifier, are transmitted from the active unit to the standby unit. In addition, periodic handshaking signals are exchanged between the two units. In the event the active unit fails, the standby unit is automatically brought on-line to process the unprocessed commands and transmit responses to the command source. When the failed unit is restored, it can become the standby unit.