Mechanism and method for distributing ISUP stacks over multiple loosely coupled processors

• US 6,507,649 B1
• Filed: 12/18/1998
• Issued: 01/14/2003
• Est. Priority Date: 12/18/1998
• Status: Expired due to Term

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Tovander, Lars A.
• Primary Examiner(s): TIEU, BENNY QUOC
• Application Number:
  US09/216,079
• Time in Patent Office: 1,488 Days
• Field of Search: 379/229, 379/230, 379/219, 379/220.01, 379/221-1-2, 379/207.02, 370/228, 370/410, 370/426, 370/467, 370/469, 370/401, 370/352-356
• US Class Current: 379/230
• CPC Class Codes: H04M 7/066 where the auxiliary connection is via an Internet Protocol network interworking of signalling system number 7 (SS7) with Internet Protocol-based session control protocols H04M7/1265, H04M7/127
• CPC Class Codes: H04Q 11/0435 Details
• CPC Class Codes: H04Q 3/0025 Provisions for signalling

Abstract

A thin ISUP layer (100) for internetworking an SS7 gateway and distributed ISUPs (90) residing on separate processors suitable for use in an SS7 network (50). The thin-ISUP layer (100) defines an operations/management module that controls circuit signaling functions between an SS7 gateway and the distributed ISUPs (90). A set of ISUP messaging functions are provided to control the sequencing of messages for distribution among the processors. Connection supervision is provided to maintain the connections between the processors. The thin ISUP layer (100) can be implemented between the MPT layer (84, 86, 88) and an ISUP layer (90) of distributed processors in the network (50).

Claims

1. In a common channel signaling system, a mechanism for distributing end-to-end call routing functions among multiple processors comprising:

an array of loosely coupled processors that communicate with each other over signaling links supporting signaling system number 7 (SS7) using an Internet Protocol (IP); and

a task distribution module comprising a layer between the MTP layer and the ISUP layer of said SS7 signaling links, said layer operably coupled to said array and configured to administer a plurality of operations/management functions over any one or a set of said array of loosely coupled processors.

2. The mechanism according to claim 1 wherein:

some of said processors are functionally organized as an SS7 gateway (SS7-GW);

some of said processors are functionally organized as an array of voice gateway access servers (VG/AS array) which communicates with said SS7-GW through a TCP/IP connection; and

wherein said layer permits said task distribution module to route message sequences from said SS7 GW to said VG/AS array through said TCP/IP connection.

3. The mechanism according to claim 2 further comprising:

a public switched telephone network (PSTN) coupled to said SS7-GW through one or more SS7 signaling links; and

a plurality of speech connections extending from said PSTN to said VG/AS so that speech data from said PSTN can reach said VG/AS array.

4. In an Internet Protocol (IP) telephony signaling network utilizing common channel signaling system number 7 (SS7), a mechanism for internetworking an SS7 Gateway and distributed ISDN User Parts (ISUPs) residing on separate processors comprising:

an operations/management module that controls circuit signaling functions between said SS7 gateway and said distributed ISUPs;

a plurality of ISUP messaging functions that control the format of both single circuit and group messages distributed between said separate processors;

a connection supervision module that maintains connections between any of said separate processors; and

wherein said operations/management module, plurality of ISUP messaging functions and connection supervision module form a protocol stack layer interspersed between the Message Transfer Part (MTP) layer and the ISUP layer implemented on said distributed processors.

5. The mechanism according to claim 4 further comprising a public switched telephone network communicably coupled to said SS7 gateway through an SS7 signaling link.

6. The mechanism according to claim 5 wherein some of said ISUPs constitute voice gateways communicably coupled to said SS7 gateway through TCP/IP connections.

7. The mechanism according to claim 6 wherein said voice gateways are communicably coupled to said PSTN through speech connection channels.

8. The mechanism according to claim 4 wherein said operations/management module includes a heartbeat sequence for determining when an entity on the network is alive.

9. The mechanism according to claim 4 wherein said operations/management module includes a circuit control sequence that can initiate and update the status of connection on the network.

10. The mechanism according to claim 4 wherein said operations/management module includes a set of MTP primitives used to distribute messages t o a processor via the SS7 Gateway.

11. The mechanism according to claim 4 wherein said plurality of ISUP messaging functions direct a message to a single processor via the SS7 Gateway.

12. The mechanism according to claim 4 wherein said plurality of ISUP messaging functions direct a message to a group of processors via the SS7 Gateway.

13. The mechanism according to claim 4 wherein said connection supervision module can generate a heartbeat supervision sequence to determine the status of a circuit.

14. The mechanism according to claim 4 wherein said connection supervision module can generate a heartbeat supervision sequence to determine whether a processor or connection in the network is up or not.

15. The mechanism according to claim 6 wherein said connection supervision module determines when said TCP/IP connection is broken.

16. The mechanism according to claim 4 wherein said connection supervision module can re-establish a connection between any of said processors.

17. A method of distributing an ISDN user part (ISUP) over multiple loosely coupled processors of an SS7 network comprising the steps of:

implementing a thin ISUP layer in between the Message Transfer Part (MTP) layer and ISUP layer of an SS7 protocol stack; and

distributing messages from a first SS7 node to a second SS7 node of said SS7 network through said thin ISUP layer.

18. The method according to claim 17 wherein the step of distributing messages is performed by distributing a message from a first SS7 node in the network to the thin ISUP layer.

19. The method according to claim 18 further comprising the step of distributing the message from the thin ISUP layer to a second node in the network.

20. The method according to claim 19 wherein the step of distributing the message to the second node is performed over a static connection coupling said first and second nodes.

21. The method according to claim 17 wherein the step of distributing messages occurs through the transmission of MTP primitive messages.

22. The method according to claim 17 preceded by the step of determining is any of the circuit connections in the network are broken.

23. The method according to claim 22 further comprising the step of blocking all circuit connections when a circuit connection is broken.

24. The method according to claim 23 further comprising the step of re-establishing a connection that is found to be broken.