Title:
TECHNIQUE FOR GRACEFUL SHUTDOWN OF A ROUTING PROTOCOL IN A NETWORK
Document Type and Number:
WIPO Patent Application WO2006006957
Kind Code:
A3
Abstract:
A graceful shutdown technique modifies a routing protocol to allow an intermediate node, such as a router (300) (802), to announce to its peer routers (peers) (804) its intention to be gracefully shutdown and removed from service in a network. By announcing its intention to be removed from service, the shutdown router closes (terminates) all connections with its peers and all original routes advertised on those connections are removed (withdrawn) from service (806). According to the inventive technique, the shutdown router may continue forwarding packets over the network for a "grace" period of time, i.e., the router maintains the validity of those original routes so that packets mapped to the routes are not dropped (at least during the grace period). The grace period also allows backup paths to be propagated to each peer and put into service prior to a final withdrawal of the shutdown router's paths from a forwarding information base of the peer (822). Thus, the grace period enables the network to continue using the shutdown router as a next hop as it re-converges to use the alternate, backup paths.
Inventors:
SCUDDER JOHN GALEN (US)
SIVABALAN MUTHURAJAH (CA)
WARD DAVID D (US)
SIVABALAN MUTHURAJAH (CA)
WARD DAVID D (US)
Application Number:
PCT/US2005/003735
Publication Date:
August 24, 2006
Filing Date:
February 07, 2005
Export Citation:
Assignee:
CISCO TECH INC (US)
International Classes:
G06F15/173; H04L45/02; G06F15/16; H04L12/56; H04L45/17; H04L45/24
Foreign References:
| US20060029076A1 | 2006-02-09 | |||
| US20040208175A1 | 2004-10-21 | |||
| US20050089015A1 | 2005-04-28 |
Other References:
See also references of EP 1723542A4
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