Restarting network reachability protocol sessions based on transport layer authentication

Patent metadata

Field	Value
Publication number	US-9300642-B2
Application number	US-94258810-A
Country	US
Kind code	B2
Filing date	Nov 9, 2010
Priority date	Nov 9, 2010
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

In an embodiment, a method comprises establishing a first data communications session with a first router. In response to receiving a first request to establish a second data communications session, a probe message that is configured to test whether the first data communications session or the first router is responsive is sent to the first router. In response to determining that the first router has not acknowledged the probe message before a probe timer has expired, and receiving a second request to establish the second data communications session, the second data communications session with the first router is established and a state for the first data communications session is deleted.

First claim

What is claimed is:

1. A method, comprising:
establishing a first data communications session between a first router and a second router;
after a reboot, a reset, or unavailability of the first router, receiving from the first router a first request to establish a second data communications session between the first router and the second router;
in response to receiving from the first router the first request to establish the second data communications session between the first router and the second router, the second router sending to the first router a probe message that is configured to test whether the first data communications session is responsive;
only in response to determining that the first router has not acknowledged the probe message before a probe timer has expired and receiving from the first router a retransmission of the first request to establish the second data communications session with the first router, the second router establishing the second data communications session with the first router and deleting a state for the first data communications session;
wherein the method is performed by one or more processors.

2. The method of claim 1 , wherein the first data communications session and the second data communications session are secured sessions; a first set of keys is used in the first data communications session; a second set of keys is used in the second data communications session; the probe message is secured with the first set of keys.

3. The method of claim 1 , wherein the first router is a Border Gateway Protocol (BGP) router; the first data communications session and the second data communications session are Transmission Control Protocol (TCP) sessions; the first data communications session and the second data communications session support a Transmission Control Protocol Authentication Option (TCP-AO).

4. The method of claim 1 , wherein the probe message is any of a BGP keepalive message, a retransmission packet of a previously transmitted packet to the first router, or a TCP probe segment.

5. The method of claim 1 , further comprising continuing to accept first session data in response to determining that the first router acknowledged the probe message before the probe timer has expired.

6. A network routing apparatus, comprising:
one or more processors;
a non-transitory computer-readable storage medium storing one or more sequences of instructions which, when executed by the one or more processors, cause the processors to perform:
establishing a first data communications session between a first router and a second router;
after a reboot, a reset, or unavailability of the first router, receiving from the first router a first request to establish a second data communications session between the first router and the second router;
in response to receiving from the first router the first request to establish the second data communications session between the first router and the second router, the second router sending to the first router a probe message that is configured to test whether the first data communications session is responsive;
only in response to determining that the first router has not acknowledged the probe message before a probe timer has expired and receiving from the first router a retransmission of the first request to establish the second data communications session, the second router establishing the second data communications session with the first router and deleting a state for the first data communications session.

7. The network routing apparatus of claim 6 , wherein the first data communications session and the second data communications session are secured sessions; a first set of keys is used in the first data communications session, a second set of keys is used in the second data communications session; the probe message is secured with the first set of keys.

8. The network routing apparatus of claim 6 , wherein the first router is a Border Gateway Protocol (BGP) router; the first data communications session and the first data communications session are Transmission Control Protocol (TCP) sessions; the first data communications session and the second data communications session support a Transmission Control Protocol Authentication Option (TCP-AO).

9. The network routing apparatus of claim 6 , wherein the probe message is any of a BGP keepalive message, a retransmission packet of a previously transmitted packet to the first router, or a TCP probe segment.

10. The network routing apparatus of claim 6 , wherein the non-transitory computer-readable storage medium further comprises instructions which, when executed by the one or more processors, cause the processors to perform continuing to accept first session data in response to determining that the first router acknowledged the probe message before the probe timer has expired.

11. A non-transitory computer-readable storage medium storing one or more sequences of instructions which, when executed by one or more processors, cause the processors to perform:
establishing a first data communications session between a first router and a second router;
after a reboot, a reset, or unavailability of the first router, receiving from the first router a first request to establish a second data communications session between the first router and the second router;
in response to receiving from the first router the first request to establish the second data communications session between the first router and the second router, the second router, sending to the first router a probe message that is configured to test whether the first data communications session is responsive;
only in response to determining that the first router has not acknowledged the probe message before a probe timer has expired and receiving from the first router a retransmission of the first request to establish the second data communications session with the first router, the second router establishing the second data communications session with the first router and deleting a state for the first data communications session.

12. The non-transitory computer-readable storage medium of claim 11 , wherein the first data communications session and the second data communications session are secured sessions; a first set of keys is used in the first data communications session; a second set of keys is used in the second data communications session; the probe message is secured with the first set of keys.

13. The non-transitory computer-readable storage medium of claim 11 , wherein the first router is a Border Gateway Protocol (BGP) router; the first data communications session and the second data communications session are Transmission Control Protocol (TCP) sessions; the first data communications session and the second data communications session support a Transmission Control Protocol Authentication Option (TCP-AO).

14. The non-transitory computer-readable storage medium of claim 11 , wherein the probe message is any of a BGP keepalive message, a retransmission packet of a previously transmitted packet to the first router, or a TCP probe segment.

15. The non-transitory computer-readable storage medium of claim 11 , further comprising instructions which, when executed by the one or more processors, cause the processors to perform continuing to accept first session data in response to determining that the first router acknowledged the probe message before the probe timer has expired.

16. A method, comprising:
establishing a first data communications session between a first router and a second router;
after a reboot, a reset, or

Assignees

• Weis Brian
• Jethanandani Mahesh
• Patel Keyur
• Ramaiah Anantha
• Cisco Tech Inc

Inventors

• Weis Brian
• Jethanandani Mahesh
• Patel Keyur
• Ramaiah Anantha

Classifications

• H04L45/033

  by updating distance vector protocols · CPC title

• H04L45/70

  Routing based on monitoring results · CPC title

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/021

  Ensuring consistency of routing table updates, e.g. by using epoch numbers · CPC title

• H04L45/28

  using route fault recovery · CPC title