Flood signaling architecture and process for provisioning communication paths

• US 20030235154A1
• Filed: 06/25/2002
• Published: 12/25/2003
• Est. Priority Date: 06/25/2002
• Status: Active Grant

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Nakata, Tsuneo
• Granted Patent: US 7,289,450 B2
• Time in Patent Office: Days
• US Class Current: 370/236
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/70 Admission control; Resource allocation
• CPC Class Codes: H04L 47/724 at intermediate nodes, e.g. resource reservation protocol [RSVP]
• CPC Class Codes: H04L 47/728 for backup paths
• CPC Class Codes: H04L 47/741 Holding a request until resources become available
• CPC Class Codes: H04L 47/746 Reaction triggered by a failure
• CPC Class Codes: H04L 47/783 Distributed allocation of resources, e.g. bandwidth brokers
• CPC Class Codes: H04L 47/821 Prioritising resource allocation or reservation requests
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data

Abstract

A method for establishing a communications path between a source node and destination node. The method includes defining a first group of network elements (NEs) suitable for use in the communications path, contemporaneously determining available resources within each of the NEs of the first group of NEs, and contemporaneously reserving those available resources appropriate to establish the communications path. The reserved resources sufficient to establish the communications path are selected, while those reserved resources not selected are released. In the absence of available resources sufficient to establish the communications path, the method is repeated using a second group of NEs suitable for establishing the communications path.

Claims

1. A method for establishing a communications path, comprising:

(a) defining a first group of network elements (NEs) suitable for use in said communications path;

(b) contemporaneously determining available resources within each of the NEs of said first group of NEs;

(c) contemporaneously reserving those available resources appropriate to establish said communications path;

(d) selecting reserved resources sufficient to establish said communications path;

(e) releasing those reserved resources not selected; and

(f) in the absence of available resources sufficient to establish said communications path, repeating steps (b)-(e) using a second group of NEs suitable for establishing said communications path.

2. The method of claim 1, wherein the second group of NEs comprises at least a portion of the first group of NEs and at least one additional network element not associated with the first group of NEs.

3. The method of claim 1, wherein the second group of NEs comprises NEs not associated with the first group of NEs.

4. The method of claim 1, wherein:

(g) in the absence of available resources sufficient to establish the communications path from the second group of NEs, repeating steps (b)-(e) using a third group of NEs suitable for establishing said communications path.

5. The method of claim 1, wherein said defining step (a) comprises defining flooding scope stages on-demand, upon receiving a request.

6. The method of claim 1, wherein said defining step (a) comprises defining flooding scope stages at the time the Path Manager (PM) is instantiated.

7. The method of claim 1, wherein said defining step (a) comprises defining flooding scope stages by listing all the links between any nodes with a distance less than a particular number from both of source and destination.

8. The method of claim 1, wherein said defining step (a) comprises defining flooding scope stages by using various routing algorithms.

10. The method of claim 1, wherein said reserving step (c) comprises:

returning a booked message from each RM to the PM to reserve the resource as one of the available resources.

11. The method of claim 10, wherein said selecting step (d) comprises:

determining whether said reserved resources form said communications path between the source and destination nodes.

12. The method of claim 11, wherein said determining step comprises:

selecting optimal reserved resources among a plurality of reserved resources to form said communications path.

13. The method of claim 12, wherein said selecting step (d) further comprises:

sending occupied messages to each optimal reserved resource forming said communications path.

14. The method of claim 1, wherein said releasing step (e) comprises:

sending release messages to those reserved resources not selected.

9. The method of step 1, wherein said determining step (b) comprises:

sending request messages from a PM at a source node to resource managers (RM) at each network element within the first group of NEs; and

returning response messages from each said RM to said PM.

15. The method of claim 9, wherein said response message comprises a failure message indicating that a particular resource in said first group of NEs is an unavailable resource for establishing said communications path.

16. The method of claim 15, wherein prior to implementing step (g), said method further comprises:

restoring an unavailable resource to an available resource in said first group of NEs.

17. The method of claim 16, wherein said restoring step comprises:

sending a notice of resource availability to said PM in said first group of NEs prior to implementing step (g).

18. The method of claim 17, wherein step (g) further comprises:

determining whether said communications path may not be established due to unavailable resources sending said failure messages.

19. The method of claim 9, wherein said response message comprises an inquiry message indicating a conflict for contention of a resource at a network element reserved by at least two PMs.

20. The method of claim 19, further comprising:

resolving said reservation conflict by selecting a PM having a priority level greater than other conflicting PMs.

21. The method of claim 20, further comprising:

in the absence of said resource being previously selected by a lower priority PM, revoking reserved resource allocation to said lower prioritized PMs.

22. The method of claim 21, further comprising:

selecting said reserved resource at said network element by said higher prioritized PM.