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. 03, 2004
Filed:
Feb. 12, 2001
Peter Van Eijk, Eemnes, NL;
Reed K. Even, Livingston, NJ (US);
Piet Van Heyningen, 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, NY (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, (2) a protection OSU of a protection circuit, and (3) one or more optical network terminals (ONTs), where an ONT has (i) a working line termination (LT) unit of the working circuit and connected to the optical splitter via a working optical fiber and (ii) a protection LT unit of the protection circuit and connected to the optical splitter via a protection optical fiber. The present invention enables fast protection switching from the working circuit to the protection circuit. The arrival times of corresponding downstream cells are measured at both the working and protection LT units of the ONT, and information related to the arrival times is transmitted from the ONT to the protection OSU. A propagation delay value is generated based on the transmitted information for use by the protection OSU for communications with the ONT if and when protection switching is implemented upon detection of a failure in the working circuit.