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:
Sep. 11, 2007
Filed:
Sep. 03, 2002
Xiaomei LU, Plano, TX (US);
Ronald P. Folkes, Dallas, TX (US);
Lance A. Visser, Dallas, TX (US);
Other;
Abstract
The HA IS-IS system provides a redundant backup IS-IS protocol instance that can seamlessly assume the function of the active IS-IS instance in the event of active MCP failure. Once the backup is online, the active synchronizes its global, interface, adjacency, neighbor, and LSP system state information. In the ongoing synchronization phase, the active and the backup maintain synchronization using a combination of explicit message updates from active to backup together with message flow-through. In the recovery phase, the operating system detects the failure of the active and notifies the backup, which assumes the active function as a standalone system without reconfiguring or interrupting traffic among peer network routers, and starts computing forwarding tables and updating routing tables.