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:
May. 26, 2009
Filed:
Dec. 20, 2005
Fumitoshi Mizutani, Tokyo, JP;
Fumitoshi Mizutani, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
The present invention has been made to realize access processing performed in accordance with synchronous/asynchronous state between processors in a fault tolerant system. In two systems that constitute a fault tolerant system, a router assigns, to an access packet transmitted from a CPU to an IO device, tag information including ID codes of access source and destination and information indicating whether the access packet is synchronous access. An access comparison section has buffers and that retain the packets from the CPU on a system basis, a tag check section that determines whether each packet is synchronous packet access based on the tag information assigned to the packets retained in the buffers, and a comparison section that outputs the packet from one system to an IO IF and discards the packet from other system in the case where the packet is synchronous access.