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:
May. 26, 2009
Filed:
Oct. 17, 2000
Gordon Mackay, Santa Clara, CA (US);
James P. Rivers, Saratoga, CA (US);
Rita Ousterhout, Palo Alto, CA (US);
Sean X. Wang, Fremont, CA (US);
John K. Chen, Sunnyvale, CA (US);
Gordon MacKay, Santa Clara, CA (US);
James P. Rivers, Saratoga, CA (US);
Rita Ousterhout, Palo Alto, CA (US);
Sean X. Wang, Fremont, CA (US);
John K. Chen, Sunnyvale, CA (US);
Cisco Technology, Inc., San Jose, CA (US);
Abstract
In a system having a plurality of nodes such as Ethernet repeaters, coupled by communication links such as cables, systems and protocols are provided for detecting and/or breaking loops. In one aspect, in response to an added link, a repeater sends a 'detect loop' message containing its address to at least one neighbor. Each repeater which receives the 'detect loop' message, in turn, sends it to its own neighbor, with the lesser of the received address and its own address. A repeater which receives a “detect loop” message containing its own address declares itself a master loop breaker and can isolate one of its ports to break the loop. In one aspect, a previously intentionally-isolated port can be re-activated, e.g., in response to the loss of a communication link which could potentially isolate one or more nodes.