Method of failure detection in an IP forwarding plane

• US 20070189177A1
• Filed: 09/26/2006
• Published: 08/16/2007
• Est. Priority Date: 08/05/2005
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Zhai, Suping
• Granted Patent: US 7,664,044 B2
• Time in Patent Office: Days
• US Class Current: 370/244
• CPC Class Codes: H04L 45/10 Routing in connection-oriented networks, e.g. X.25 or ATM
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]

Abstract

A method of failure detection on an Internet Protocol (IP) forwarding plane, which includes: IP nodes of the two ends obtain Bidirectional Forwarding Detection (BFD) identifier information which is used in the BFD, moreover start a BFD session, encapsulate and transport a BFD packet between the IP nodes running the BFD session and implement the failure detection according to the BFD packet transported between the IP nodes. The method of this invention realizes the failure detection via starting the BFD session and via transporting the BFD packet between the inter-domain IP nodes or the intra-domain IP nodes.

Claims

1. A method for implementing a failure detection on an Internet Protocol (IP) forwarding plane, comprising:

IP nodes obtaining Bidirectional Forwarding Detection (BFD) identifier information which is used in the BFD, and starting a BFD session;

the IP nodes encapsulating a BFD packet and transporting the packet between the IP nodes running the BFD session;

detecting a failure according to the BFD packet transported between the IP nodes.

2. The method according to claim 1, wherein the IP nodes are two inter-domain IP nodes and the route between the IP nodes is populated dynamically, the IP nodes obtain the BFD identifier information and start the BFD session comprises:

obtaining the BFD identifier information via an exchanged Border Gateway Protocol (BGP) packet between the IP nodes, and starting the BFD session between the IP nodes.

3. The method according to claim 2, wherein the BFD identifier information is carried in a new Capability Code of a BGP OPEN packet;

the new Capability Code is added in a Capability option of the BGP OPEN packet.

4. The method according to claim 1, wherein the IP nodes are two inter-domain IP nodes and the route between the IP nodes is populated dynamically, the IP nodes obtain the BFD identifier information and start the BFD session comprises:

configuring the corresponding BFD identifier information in the IP nodes respectively, and starting the BFD session between the IP nodes via the configured BFD identifier information.

5. The method according to claim 1, wherein the IP nodes are two inter-domain IP nodes or two intra-domain IP nodes, and the route between the IP nodes is configured statically, the IP nodes obtain the BFD identifier information and start the BFD session comprises:

configuring the corresponding BFD identifier information in the IP nodes respectively, and starting the BFD session between the IP nodes via the configured BFD identifier information.

6. The method according to claim 1, wherein the IP nodes are two inter-domain IP nodes or two intra-domain IP nodes, and the route between the IP nodes is configured statically, the IP nodes obtain the BFD identifier information and start the BFD session comprises:

obtaining the BFD identifier information via an exchanged Internet Control Message Protocol v4 (ICMPv4) packet between the IP nodes, and starting the BFD session between the IP nodes.

7. The method according to claim 6, wherein the BFD identifier information is carried in a new My Discriminator field of an ICMPv4 Information Request of the ICMPv4 packet, or the BFD identifier information is carried in the new My Discriminator field of an ICMPv4 Information Reply Message of the ICMPv4 packet.

8. The method according to claim 2, wherein the IP nodes obtain the BFD identifier information and start the BFD session comprises:

starting the BGP session after the BFD session startup.

9. The method according to claim 2, wherein a C bit of the BFD packet is used for determining whether the BFD session and a control layer are in correlation or not;

and the IP nodes obtain the BFD identifier information and start the BFD session comprises;

the peer IP node of the BFD session determining whether to stop a control layer BGP graceful restart process or not according to the C bit information, and if the C bit is reset and the BFD session detects the failure, stopping the BGP graceful restart process;

otherwise, if the C bit is configured and the BFD session detects the failure, continuing progress of the BGP graceful restart.

10. The method according to claim 5, before the BFD session is started by the IP nodes which has obtained the BFD identifier information, further comprising:

after the IP nodes obtaining the BFD identifier information, the IP nodes determining whether to start the BFD to implement the failure detection on a static route forwarding plane based. on requirements.

11. The method according to claim 6, before the BFD session is started by the IP nodes which has obtained the BFD identifier information, further comprising:

after the IP nodes obtaining the BFD identifier information, the IP nodes determining whether to start the BFD to implement the failure detection on a static route forwarding plane based on requirements.

12. The method according to claim 1, wherein, the IP nodes encapsulate the BFD packet by is:

encapsulating the packet by a User Datagram Protocol (UDP) packet.