Method and apparatus for coordinating routing parameters via a back-channel communication medium

• US 20020075813A1
• Filed: 09/20/2001
• Published: 06/20/2002
• Est. Priority Date: 10/17/2000
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Incorporated
• Inventors: Karam, Mansour J., Baldonado, Omar C., Finn, Sean P., Lloyd, Michael A., McGuire, James G., Madan, Herbert S., Villaverde, Jose-Miguel Pulido
• Granted Patent: US 7,349,994 B2
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 41/508 based on type of value added network service under agreement
• CPC Class Codes: H04L 41/5096 wherein the managed service relates to distributed or central networked applications
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 43/0835 One way packet loss
• CPC Class Codes: H04L 43/0841 Round trip packet loss
• CPC Class Codes: H04L 43/0858 One way delays
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 43/087 Jitter
• CPC Class Codes: H04L 43/0882 Utilisation of link capacity
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/123 Evaluation of link metrics techniques for monitoring network metrics H04L43/08
• CPC Class Codes: H04L 45/124 using a combination of metrics
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/11 : Identifying congestion
• CPC Class Codes: H04L 47/20 : Traffic policing
• CPC Class Codes: H04L 47/283 : in response to processing delays, e.g. caused by jitter or round trip time [RTT]

Abstract

Systems and methods are described for enabling routers to coordinate via a back-channel communication medium. The information exchanged over the back-channel is used to increase the number of paths considered for the routers during route optimization. The Decision Makers may assert routes and prefixes to the routers under their control. This may be done via a Border Gateway Protocol (BGP) feed. The Decision Makers, in turn, communicate separately with one another, in order to coordinate routing policy amongst themselves. This coordination may be performed over a back-channel, which may take the form of physical or logical connections between the Decision Makers.

Claims

1. A communications back-channel, for coordinating routing decisions, the communications back channel comprising:

a plurality of networking devices;

a plurality of routing intelligence units, wherein each of the plurality of the plurality of routing intelligence units includes software for controlling a distinct subset of the plurality of networking devices, each of the plurality of routing intelligence units further including;

one or more processes for controlling the distinct subset of networking devices; and

one or more coordination processes for exchanging routing parameters with the plurality of routing intelligence units.

2. The communications back-channel of claim 1, wherein the one or more processes for controlling the distinct subset of networking devices are Border Gateway Protocol (BGP) sessions.

3. The communications back-channel of claim 2, wherein each of the routing intelligence units is a route-reflector client.

4. The communications back-channel of claim 3, wherein each of the distinct subset of networking devices is a route reflector to the route reflector client.

5. The communications back-channel of claim 1, wherein the one or more coordination process in each of the routing intelligence units includes BGP sessions.

6. The communications back-channel of claim 5, wherein the BGP sessions in the one or more coordination processes of each of the routing intelligence units includes:

at least one BGP process; and

at least one BGP stack, such that the at least one BGP stack exchanges routing parameters between the routing intelligence unit and the at least one BGP process, and the at least one BGP process exchanges routing parameters with the plurality of routing intelligence units.

7. The communications back-channel of claim 6, wherein the at least one BGP stack is a route reflector client, and the at least one BGP process is a route reflector.

8. The communications back-channel of claim 6, wherein the routing parameters include local path performance characteristics.

9. The communications back-channel of claim 6, wherein the routing parameters include performance scores for routes.

10. The communications back-channel of claim 9, wherein the performance scores are exchanged via a Local Preference field.

11. The communications back-channel of claim 1, further comprising:

a plurality of communication links directly coupling the plurality of routing intelligence units, wherein the plurality of communication links are dedicated exclusively for exchanging routing parameters between the plurality of routing intelligence units.

12. The communications back-channel of claim 11, wherein the plurality of communication links are at least partially comprised of physical links between the plurality of routing intelligence units.

13. The communications back-channel of claim 11, wherein the plurality of communication links are at least partially comprised of logical links between the plurality of routing intelligence units.

15. The method of claim 14, further comprising:

receiving a second plurality of routes for a second plurality of prefixes via the dedicated mesh.

16. The method of claim 15, further comprising:

receiving a plurality of performance scores for the second plurality of routes.

17. The method of claim 16, wherein the plurality of performance scores are included in one or more Local Preferences fields in a BGP feed.

18. The method of claim 16, further comprising:

applying penalties to each of the plurality of performance scores.

19. The method of claim 14, wherein the asserting the first plurality of preferred routes is performed via a BGP feed to the subset of routers.

20. The method of claim 14, wherein the plurality of local performance scores are sent via a BGP feed to the dedicated mesh.

21. The method of claim 14, wherein the dedicated mesh is at least partially comprised of physical links between the plurality of decision makers.

22. The method of claim 14, wherein the dedicated mesh is at least partially comprised of logical links between the plurality of decision makers.

14. A method of exchanging routing parameters amongst a plurality of decision makers, each decision maker controlling a distinct subset of a plurality of routers, wherein the plurality of decision makers are in communication via a dedicated mesh, the method comprising:

asserting a first plurality of preferred routes for a first plurality of prefixes to the subset of routers; and

concurrent with the asserting the first plurality of preferred routes, sending a plurality of local performance scores for the first plurality of routes to the plurality of decision makers via the dedicated mesh.