Electrical computers and digital processing systems: multicomput – Computer-to-computer data routing – Routing data updating
Reexamination Certificate
2000-02-24
2004-05-18
Wiley, David (Department: 2143)
Electrical computers and digital processing systems: multicomput
Computer-to-computer data routing
Routing data updating
C370S228000, C714S011000, C700S079000, C700S003000, 36, 36
Reexamination Certificate
active
06738826
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to computer networks and more particularly to systems and methods for upgrading packet processing software without interfering with packet flow.
Routers are internetworking devices that are typically used to connect similar and heterogeneous network segments into internetworks. A typical router includes various interfaces that send and receive packets. The router receives a given packet through a first interface, processes the packet to determine how to best forward the packet to its destination, and then based on this determination transmits the packet through a selected second interface.
In a high speed data communication network, a router will handle a very large and continuous flow of packets. Any sustained interruption of router operation may adversely affect network performance due to increased latency or even loss of packets.
Many popular types of routers operate under the control of packet processing software. The packet processing software directly manipulates the individual packets to be forwarded by the router. As with any software controlled device, it is sometimes desirable or necessary to replace or upgrade the software. A problem arises in that changing software requires halting packet processing because it is the software that directly manipulates the packet. Systems and methods for replacing router software while minimizing impact on network operation are needed.
SUMMARY OF THE INVENTION
Systems and methods for replacing software controlling active routers while minimizing impact on network operation are provided by virtue of one embodiment of the present invention. The software replacement process takes advantage of packet processor redundancy. In one embodiment, an active packet switching device to be reprogrammed is de-activated and a redundant packet switching device takes over. The no longer active packet switching device is reprogrammed before being reactivated.
A first aspect of the present invention provides a computer-implemented method for replacing an active packet switching device without interfering with packet flow. The method includes receiving a failover message at a currently active packet switching device (A), transferring protocol state information from the packet switching device (A) to a currently inactive packet switching device (B), de-activating the packet switching device (A) and activating the packet switching device (B).
A second aspect of the present invention provides a computer-implemented method for reprogramming an active packet switching device without interfering with packet flow. The method includes: de-activating a current packet switching device (A) and activating a standby packet switching device (B) to handle packet flow previously handled by the packet switching device (A), thereafter reprogramming the packet switching device (A), and thereafter deactivating the packet switching device (B) and re-activating the packet switching device (A).
REFERENCES:
patent: 5089958 (1992-02-01), Horton et al.
patent: 5136498 (1992-08-01), McLaughlin et al.
patent: 5157663 (1992-10-01), Major et al.
patent: 5473599 (1995-12-01), Li et al.
patent: 5590724 (1997-01-01), Verdgikovsky
patent: 5815668 (1998-09-01), Hashimoto
patent: 5870557 (1999-02-01), Bellovin et al.
patent: 5914953 (1999-06-01), Krause et al.
patent: 5919266 (1999-07-01), Sud et al.
patent: 5963448 (1999-10-01), Flood et al.
patent: 6118768 (2000-09-01), Bhatia et al.
patent: 6229787 (2001-05-01), Byrne
patent: 6236999 (2001-05-01), Jacobs et al.
patent: 6263452 (2001-07-01), Jewett et al.
patent: 6285656 (2001-09-01), Chaganty et al.
patent: 6286048 (2001-09-01), Moberg
patent: 6389555 (2002-05-01), Purcell et al.
patent: 6397385 (2002-05-01), Kravitz
patent: 6457138 (2002-09-01), Lesser et al.
patent: 6460146 (2002-10-01), Moberg et al.
patent: 6490246 (2002-12-01), Fukushima et al.
U.S. patent application Ser. No. 09/205,577, Moberg et al., filed Dec. 1998.
U.S. patent application Ser. No. 09/205,554, Moberg, filed Dec. 1998.
Jack Jenney, “Dual RSP—High System Availability SW Functional Spec”, Oct. 6, 1995, Cisco Systems, Inc.
Kon Ronnie
Moberg Kenneth
Boutah Alina A.
Cisco Technology Inc.
Ritter Lang & Kaplan LLP
Wiley David
LandOfFree
Router software upgrade employing redundant processors does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Router software upgrade employing redundant processors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Router software upgrade employing redundant processors will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3242329