Transport control protocol sequence number recovery in stateful devices
AssigneeCisco Technology, Inc.
InventorsAndrew E. Ossipov, Kent Leung
Life of this patent
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Abstract
Techniques are presented herein for optimizing network traffic exchanged between devices in a network. A firewall device in a network detects a firewall failure event. In response to detecting the firewall failure event, the firewall device changes from a standby state to an active state in managing a network connection between a source device and a destination device in the network. The firewall device generates a synchronization message and sends the synchronization message to the destination device. The firewall device receives from the destination device a response message that includes synchronization information.
Claims21
A method comprising:
- at a first firewall device in a network, detecting a firewall failure event of second firewall device;
- in response to detecting the firewall failure event of the second firewall device, changing a state of the first firewall device from a standby state to an active state in managing a network connection between a source device and a destination device in the network;
- generating at the first firewall device a synchronization message;
- sending the synchronization message from the first firewall device to the destination device;
- and
- receiving at the first firewall device a response message from the destination device that includes synchronization information.
An apparatus comprising:
- a network interface unit configured to enable network communications;
- and
- a processor coupled to the network interface unit, and configured to:
- detect a firewall failure event of a firewall device other than said apparatus;
- change a state of the apparatus from a standby state to an active state in response to detecting the firewall failure event of the firewall device to manage a network connection between a source device and a destination device in a network;
- generate a synchronization message;
- cause the synchronization message to be sent to the destination device;
- and
- obtain from the network interface unit a response message received from the destination device, the response message including synchronization information.
A computer-readable storage media encoded with software comprising computer executable instructions and when the software is executed operable to:
- detect at a first firewall device a firewall failure event of a second firewall device;
- change a state of the first firewall device from a standby state to an active state in managing a network connection between a source device and a destination device in a network in response to detection of the firewall failure event of the second firewall device;
- generate a synchronization message at the first firewall device;
- cause the synchronization message to be sent from the first firewall device to the destination device;
- and
- obtain at the first firewall device a response message received from the destination device, the response message including synchronization information.
Dependencies are inferred from the claim text.