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:
Oct. 19, 2004
Filed:
Dec. 21, 1999
Herman Levenson, Palo Alto, CA (US);
Jonathan Davar, Los Altos Hills, CA (US);
Ajit Sanzgiri, Cupertino, CA (US);
Thomas J. Edsall, Cupertino, CA (US);
Chingwei Chang, Sunnyvale, CA (US);
Rong-Lung Lue, Saratoga, CA (US);
Saravanakumar Rajendran, San Jose, CA (US);
Tuan Thanh Nguyen, Milpitas, CA (US);
Claudette Lucille Surma, Fremont, CA (US);
Cisco Technology, Inc., San Jose, CA (US);
Abstract
A technique enables learning and switching of frames between line cards that are interconnected by a switch fabric of a distributed network switch. The network switch comprises a router and a plurality of forwarding engines, each having an associated forwarding table. The distributed learning and switching technique configures (i) the router to issue an extra copy of a routed frame to an ingress card having a port attached to the source of the frame; (ii) the router to ensure that the contents of a source index field of the routed frame header indicate that the frame originated from the ingress card; (iii) the router to assert a shortcut bit in the header of the routed frame; (iv) a forwarding engine on an egress card having a port attached to the destination of the frame to generate and issue a media access control notification frame to the ingress card and (v) a forwarding engine on the ingress card to mark an established entry in a layer 2 (L2) portion of its forwarding table as ineligible for normal L2 aging policies.