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:
Jul. 17, 2001
Filed:
Aug. 28, 1998
Michael John Seaman, Mountain View, CA (US);
Vipin K. Jain, Santa Clara, CA (US);
3Com Corporation, Santa Clara, CA (US);
Abstract
An improvement to the spanning tree protocol provides for identifying a port on the bridge in the alternate port role which qualifies as a next best root port. Upon detection of a failure at the root port, or other event causing a change in the root port to a blocking state, the next best root port transitions to the root port role, and forwarding state immediately without traversing the listening and learning states of the standard protocol. Also, in networks in which there is a possibility of shared media links between bridges, ports that have the alternate port role, and connect to a LAN which is also connected through a designated port on the same bridge are identified as a backup. The algorithm prevents such backup ports from transitioning to the forwarding state before the designated port connected to the same LAN segment transitions to a blocking state.