Methods, systems, and computer program products for dynamically adjusting load sharing distributions in response to changes in network conditions

• US 20060067503A1
• Filed: 06/07/2005
• Published: 03/30/2006
• Est. Priority Date: 09/10/2004
• Status: Active Grant

• Current Assignee: Tekelec Global, Inc. (Oracle Corporation)
• Original Assignee: Tekelec
• Inventors: Marsico, Peter J., Caugherty, Jill H., Khungar, Komal G.
• Granted Patent: US 7,633,969 B2
• Time in Patent Office: Days
• US Class Current: 379/221.70
• CPC Class Codes: H04M 7/06 using auxiliary connections for control or supervision , e.g. where the auxiliary connection is a signalling system number 7 link
• CPC Class Codes: H04Q 2213/13097 Numbering, addressing
• CPC Class Codes: H04Q 2213/13164 Traffic (registration, measurement,...)
• CPC Class Codes: H04Q 2213/13166 Fault prevention
• CPC Class Codes: H04Q 2213/13176 Common channel signaling, CCS7
• CPC Class Codes: H04Q 3/0025 Provisions for signalling

Abstract

A signaling network routing node, such as a signaling system 7 (SS7)/Internet protocol (IP) gateway, is adapted to perform global title translation (GTT) or other processing on received signaling messages and route the signaling messages to a member of a load sharing group using a threshold-based weighted load sharing algorithm. In the event that one of the signaling destinations in the load sharing group becomes unavailable, signaling message traffic is redistributed evenly among the remaining available members of the load sharing group in a manner such that a maximum load sharing weight threshold value associated with each group member is not exceeded. If a load sharing group member becomes unavailable, and the resulting recalculated load sharing weights of the remaining available members sum to less than 100%, then load sharing weights for the group are normalized, and a maximum message rate capacity threshold associated with each group member is used to determine whether the discarding of messages is required.

Claims

1. A method for dynamically load sharing signaling messages among mated signaling destinations in response to changes in network operating conditions, the method comprising:

(a) defining a group of signaling destinations as a load sharing (LS) group;

(b) assigning each member of the LS group a nominal load sharing weight (LSW) and a maximum load sharing weight threshold (MWT);

(c) in response to a LS group member becoming unavailable to receive signaling message traffic, distributing the LSW associated with the unavailable member among the remaining available members in a manner such that the MWT thresholds associated with each of the remaining available members are not exceeded; and

(d) load sharing received signaling message traffic destined for a member of the LS group in accordance with each available group member'"'"'s LSW.

2. The method of claim 1 wherein defining a group of signaling destinations as a LS group includes defining a group of signaling system 7 (SS7) signaling points as a LS group.

3. The method of claim 2 wherein defining a group of SS7 signaling points as a LS group includes defining a group of SS7 service control points.

4. The method of claim 1 wherein defining a group of signaling destinations as a LS group includes defining a group of Internet protocol (IP)-based signaling destinations.

5. The method of claim 1 wherein each nominal LSW is expressed as a percentage of signaling message traffic.

6. The method of claim 1 wherein each MWT is expressed as a percentage of signaling message traffic.

7. The method of claim 1 comprising determining whether the sum of available LS group member LSW values is less than 100%, and, in response to determining that the sum of the available LS group member LSW values is less than 100%, normalizing the LSW values associated with the available group members.

8. The method of claim 1 comprising determining whether load sharing a signaling message to a member of the LS group will exceed a maximum message rate receipt capacity threshold (MCT) associated with the member, and in response to determining that load sharing a received signaling message to a member of the LS group will exceed the (MCT) associated with the member, attempting to load share the message to another member of the LS group.

9. The method of claim 8 wherein attempting to load share the message includes determining whether other members of the LS group can receive the message without exceeding their MCTs, and in response to determining that no other members of the LS group can receive the message without exceeding their MCTs thresholds, buffering the message.

10. The method of claim 8 wherein attempting to load share the message includes determining whether other members of the LS group can receive the message without exceeding their MCTs, and in response to determining that no other members of the LS group can receive the message without exceeding their associated MCT thresholds, discarding the message.

11. The method of claim 10 comprising generating a network management message associated with discarding of the message.

12. The method of claim 1 wherein the received signaling message traffic includes SS7 signaling connection control part (SCCP) message traffic.

13. The method of claim 1 wherein the received signaling message traffic includes Internet Engineering Task Force (IETF) SIGTRAN SCCP user adaptation layer (SUA) message traffic.

14. The method of claim 1 wherein the received signaling message traffic includes session initiation protocol (SIP) message traffic.

15. The method of claim 1 wherein steps (a)-(d) are performed at a network routing node.

16. The method of claim 15 wherein the network routing node comprises an SS7 signal transfer point.

17. The method of claim 15 wherein the network routing node comprises an SS7/IP signaling gateway.

18. The method of claim 1 wherein load sharing the signaling message traffic includes load sharing the signaling message traffic after performing global title translation for the signaling message traffic.

19. The method of claim 1 comprising, in response to a LS group member becoming available to receive signaling message traffic, resetting the LSW values of the available members to their nominal LSW values.

20. The method of claim 19 comprising, in response to determining that the sum of the LSW values is less than 100%, increasing the LSW values in a manner such that the MWT thresholds associated with each of the available members are not exceeded.

21. A system for load sharing signaling messages and dynamically adjusting load sharing distribution weights in response to changes in network operating conditions, the system comprising:

(a) a first communications module for receiving a signaling message that is destined for a signaling destination, which is a member of a load sharing group;

(b) a load sharing function for;

(i) maintaining load sharing weight (LSW) assignment information for each member of the load sharing group;

(ii) maintaining maximum load sharing weight threshold (MWT) information for each member of the load sharing group;

(iii) dynamically adjusting LSW assignments in response to a change in availability status of a group member such that the resulting LSW for each available group member does not exceed the associated MWT for each member; and

(iv) selecting a member of the load sharing group to receive the signaling message; and

(c) a second communications module for communicating the signaling message to the selected member of the load sharing group.

22. The system of claim 21 wherein the first and second communications modules and the load sharing function are components of a network routing node.

23. The system of claim 22 wherein the network routing node comprises a signaling system 7 (SS7) signal transfer point.

24. The system of claim 22 wherein the network routing node comprises an SS7/Internet protocol (IP) signaling gateway.

25. The system of claim 21 wherein the first communications module comprises an SS7 link interface module.

26. The system of claim 21 wherein the second communications module comprises an SS7/IP data communication module.

27. The system of claim 21 wherein the signaling destination comprises an SS7 signaling point.

28. The system of claim 21 wherein the signaling destination comprises an IP-based signaling point.

29. The system of claim 28 where the IP-based signaling points that comprise the load sharing group share the same SS7 network address.

30. The system of claim 21 comprising a database services module operatively associated with the first communications module, wherein the load sharing function resides on a the database services module.

31. The system of claim 21 where the load sharing function resides on the first communications module.

32. The system of claim 21 wherein the load sharing function resides on the second communications module.

33. The system of claim 21 wherein the load sharing function, in response to determining that the sum of the available LS group member LSW values is less than 100%, is adapted to normalize the LSW values associated with the available group members.

34. The system of claim 21 wherein the load sharing function is adapted to determine whether load sharing a received signaling message to a member of the LS group will exceed a maximum message receipt rate capacity threshold (MCT) associated with the member, and in response to determining that the MCT for the member will be exceeded, the load sharing function is adapted to attempt to load share the message to another member of the LS group.

35. The system of claim 34 wherein the load sharing function, in response to determining that no other members of the LS group can receive the message without exceeding their associated MCT thresholds, is adapted to buffer the message.

36. The system of claim 21 wherein the load sharing function, in response to determining that a LS group member has become available, is adapted to reset the LSW values of all of the available group members to their respective nominal LSW values.

37. The system of claim 36 wherein the load sharing function, in response to determining that the sum of the LSW values is less than 100%, is adapted to increase the LSW values in a manner such that the MWT thresholds associated with each of the available members are not exceeded.

38. The system of claim 24 wherein the load sharing function is adapted to communicate the signaling message to the first communications module and wherein the first communications module is adapted to communicate the signaling message to the selected member of the load sharing group.

39. A computer program product comprising computer-executable instructions embodied in a computer-readable medium for performing steps comprising:

(a) defining a group of signaling destinations as a load sharing (LS) group;

(b) assigning each member of the LS group a nominal load sharing weight (LSW) and a maximum load sharing weight threshold (MWT);

(c) in response to a LS group member becoming unavailable to receive signaling message traffic, distributing the LSW associated with the unavailable member among the remaining available members in a manner such that the MWT thresholds associated with each of the remaining available members are not exceeded; and

(d) load sharing received signaling message traffic destined for a member of the LS group in accordance with each available group member'"'"'s LSW.