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. 01, 2011
Filed:
Mar. 31, 2006
Kazuo Takagi, Tokyo, JP;
Masahiro Sakauchi, Tokyo, JP;
Daisaku Ogasahara, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
In a multi-ring network with a plurality of rings to which RPR is applied connected, high-speed failure recovery is enabled when a failure occurs between the rings. The contact nodes-and-connected to the living inter-linkperiodically transmit and receive a KeepAlive signal to/from each other. Then, when a KeepAlive signal fails to arrive for a fixed time period, determination is made that the inter-linkdevelops a fault to broadcast-transmit an inter-link failure notification RPR-MAC frame indicative of failure occurrence on the inter-link to each node. A contact node as a transmission source of the inter-link failure notification RPR-MAC frame and each node having received the inter-link failure notification RPR-MAC frame immediately flush learning contents of their own learning data bases. A contact node connected to the spare inter-linkswitches the spare inter-linkto a forwarding state.