Verification of network paths using two or more connectivity protocols

• US 8,797,886 B1
• Filed: 12/13/2010
• Issued: 08/05/2014
• Est. Priority Date: 01/30/2006
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Kompella, Kireeti
• Primary Examiner(s): Ngo, Ricky
• Assistant Examiner(s): SAMUEL, DEWANDA A
• Application Number:
  US12/966,869
• Time in Patent Office: 1,331 Days
• Field of Search: 370/400, 370/401, 370/396, 370/242, 370/248
• US Class Current: 370/248
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/70 Routing based on monitoring results

Abstract

Techniques are described for verifying a status of a set of paths through a computer network for two or more connectivity protocols. For example, a node uses a first connectivity protocol to concurrently learn information that will cause packets conforming to the first connectivity protocol and packet conforming to a second connectivity protocol to traverse a set of paths through a computer network. After learning this information, the node may verify a status of each of the paths using the first connectivity protocol. In addition, the node may verify a status of each of the paths using the second connectivity protocol. By verifying the status of the paths using both the first and the second connectivity protocols, the node may be able to quickly and accurately determine whether a path has failed.

Claims

1. A method comprising:

receiving, with an intermediate network device along a label switched path (LSP) having a plurality of alternative paths, a request that conforms to a first connectivity protocol to perform a first verification of the LSP;

generating, with the intermediate network device, first packet header information that conforms to the first connectivity protocol and second packet header information that conforms to a second connectivity protocol, wherein the first packet header information and the second packet header information are associated with two or more of the plurality of alternative paths of the LSP; and

sending the first packet header information and the second packet header information from the intermediate network device to a network device in a single reply packet that conforms to the first connectivity protocol,

wherein the first packet header information and the second packet header information in the reply packet instruct the network device with packet header information to form packets and direct the packets along the individual paths in accordance with both the first connectivity protocol and the second connectivity protocol.

2. The method of claim 1, wherein the first connectivity protocol is a Label Switched Path (LSP) Ping protocol and the second connectivity protocol is a Bidirectional Forwarding Detection protocol.

3. The method of claim 2, wherein the request comprises an exploration packet conforming to the LSP Ping protocol and the reply packet comprises an exploration response.

4. The method of claim 3,

wherein the exploration packet specifies a set of variable information in accordance with the LSP Ping protocol, and

wherein generating first packet header information comprises generating the first packet header information to include variable information for the LSP Ping protocol associated with a path from the intermediate network device to a second network device along one of the paths.

5. The method of claim 3,

wherein the exploration packet specifies a set of variable information in accordance with the Bidirectional Forwarding Detection protocol, and

wherein generating second packet header information comprises generating the second packet header information to include variable information for the BFD protocol associated with a path from the intermediate network device to a second network device along one of the paths.

6. A network device comprising:

a processor; and

an exploration response module executing on the processor to receive an exploration packet in accordance with a first connectivity protocol,

wherein the exploration response module generates first packet header information that conforms to the first connectivity protocol and second packet header information that conforms to a second connectivity protocol,

wherein the first packet header information and the second packet header information is associated with two or more of the plurality of alternative paths of a label switched path (LSP),

wherein the first packet header information and the second packet header information specify respective packet header information necessary to direct packets along the individual paths in accordance with both the first connectivity protocol and the second connectivity protocol, and

wherein the exploration response module sends the first packet header information and the second packet header information from the intermediate node to a network device in a single reply packet that conforms to the first connectivity protocol.

7. The network device of claim 6, wherein the first connectivity protocol is a Label Switched Path (LSP) Ping protocol and the second connectivity protocol is a Bidirectional Forwarding Detection (BFD) protocol.

8. The network device of claim 7, wherein the exploration packet conforms to the LSP Ping protocol and the reply packet comprises an exploration response.

9. The network device of claim 8,

wherein the exploration packet specifies a set of variable information in accordance with the LSP Ping protocol, and

wherein the exploration response module generates the first packet header information to include variable information for the LSP Ping protocol associated with a path from the network device to a third network device along one of the paths.

10. The network device of claim 8,

wherein the exploration packet specifies a set of variable information in accordance with the Bidirectional Forwarding Detection protocol, and

wherein generating second packet header information comprises generating the second packet header information to include variable information for the BFD protocol associated with a path from the intermediate network device to a third network device along one of the paths.

11. A non-transitory computer-readable medium comprising instructions to cause a network device to:

receive a request that conforms to a first connectivity protocol to perform a first verification of a label switched path (LSP);

generate first packet header information that conforms to the first connectivity protocol and second packet header information that conforms to a second connectivity protocol; and

send the first packet header information and the second packet header information in a single reply packet that conforms to the first connectivity protocol, wherein the first packet header information and the second packet header information in the reply packet specify respective packet header information necessary to direct packets along the individual paths in accordance with both the first connectivity protocol and the second connectivity protocol.

12. The non-transitory computer-readable medium of claim 11, wherein the first connectivity protocol is a Label Switched Path (LSP) Ping protocol and the second connectivity protocol is a Bidirectional Forwarding Detection protocol.

13. The non-transitory computer-readable medium of claim 12, wherein the request comprises an exploration packet conforming to the LSP Ping protocol and the reply packet comprises an exploration response.

14. The non-transitory computer-readable medium of claim 13,

wherein the exploration packet specifies a set of variable information in accordance with the LSP Ping protocol, and

wherein the instructions cause the network device to generate the first packet header information to include variable information for the LSP Ping protocol associated with a path from the network device to a second network device along one of the paths.

15. The non-transitory computer-readable medium of claim 13,

wherein the exploration packet specifies a set of variable information in accordance with the Bidirectional Forwarding Detection protocol, and

wherein the instructions cause the network device to generate the second packet header information to include variable information for the BFD protocol associated with a path from the network device to a second network device along one of the paths.