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:
Oct. 09, 2007
Filed:
Sep. 03, 2003
Tatsuya Shiragaki, Tokyo, JP;
Naoya Henmi, Tokyo, JP;
Makoto Nishio, Tokyo, JP;
Hitoshi Takeshita, Tokyo, JP;
Hirofumi Shimomura, Tokyo, JP;
Tatsuya Shiragaki, Tokyo, JP;
Naoya Henmi, Tokyo, JP;
Makoto Nishio, Tokyo, JP;
Hitoshi Takeshita, Tokyo, JP;
Hirofumi Shimomura, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Multiple working paths are established on each working rings and multiple protection paths are established on each of multiple protection rings. A working path on a first working ring spans across first and second nodes for signal transmission in a first direction of the ring, and a working path on a second working ring spans across the first and second nodes for signal transmission in a second, opposite direction of the ring. A protection path on a first protection ring spans across the first and second nodes for signal transmission in said second direction, and a protection path on a second protection ring spans across the first and second nodes for signal transmission in said first direction. The first and second nodes normally use the working paths, respectively. When one of the working paths fails, the first and second nodes use a corresponding protection path.