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:
Feb. 10, 2004
Filed:
Feb. 17, 1999
Steven S. Gorshe, Beaverton, OR (US);
Zhone Technologies, Inc., Oakland, CA (US);
Abstract
A mechanism for 1:1, 1+1, and UPSR path-switched protection switching, particularly for optical interface units in synchronous optical network (SONET) multiplexer equipment. A working unit and a standby unit pair protect each other in the event of a failure of the working unit or the failure of the span connected to the working unit if both the working and standby units are connected to different spans. Each unit is made responsible for detecting failures of the span that it receives and is primarily responsible for detecting a fault within the unit's own hardware or software. When a unit or span failure is detected, switch control is localized to the two units (i.e. the working and standby unit) which eliminates the need for a third control unit, which reduces processing time and reduces the system hardware. Moreover, this feature allows distributed control of the system protection so that protection switching on multiple unit pairs can be performed in parallel rather than in a serial manner by a common control unit. Both unit and span failures are handled through the same signal pair and simple hardware.