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:
Mar. 15, 2005
Filed:
Feb. 12, 2001
Peter Van Eijk, Eemnes, NL;
Reed K. Even, Livingston, NJ (US);
Piet Van Hevingen, Almere, NL;
Song Jiang, Whippany, NJ (US);
Kyeong-soo Kim, San Jose, CA (US);
Woojune Kim, Seoul, KR;
Fengkun Liu, Great Neck, NY (US);
Yong-kwan Park, Annandale, NJ (US);
Peter Van Eijk, Eemnes, NL;
Reed K. Even, Livingston, NJ (US);
Piet Van Hevingen, Almere, NL;
Song Jiang, Whippany, NJ (US);
Kyeong-Soo Kim, San Jose, CA (US);
Woojune Kim, Seoul, KR;
Fengkun Liu, Great Neck, NY (US);
Yong-Kwan Park, Annandale, NJ (US);
Lucent Technologies Inc., Murray Hill, NJ (US);
Abstract
An optical network has an optical splitter connected to (1) a working optical subscriber unit (OSU) of a working circuit via a working optical fiber, (2) a protection OSU of a protection circuit via a protection optical fiber, and (3) one or more optical network terminals (ONTs). The present invention enables fast protection switching from the working OSU to the protection OSU. In one embodiment, the arrival times of corresponding upstream ranging reply PLOAM cells are measured at both the working and protection OSUs during ranging operations of the working OSU. In another embodiment, a cell delineation procedure is initiated at the protection OSU during normal, non-ranging operations of the working OSU to enable the protection OSU to correctly delineate upstream cells and the arrival times of corresponding upstream cells are then measured at both the working and protection OSUs. In either case, a propagation delay value is generated based on the measured arrival times for use by the protection OSU for communications with the one or more ONTs if and when protection switching is implemented upon detection of a failure in the working circuit, possibly without requiring the protection OSU to perform any ranging for the one or more ONTs.