Systems and methods for communicating messages among signaling system 7 (SS7) signaling points (SPs) and internet protocol (IP) nodes using signal transfer points (STPS)

• US 6,324,183 B1
• Filed: 12/04/1998
• Issued: 11/27/2001
• Est. Priority Date: 12/04/1998
• Status: Expired due to Term

• Current Assignee: Tekelec Global, Inc. (Oracle Corporation)
• Original Assignee: Tekelec
• Inventors: Brendes, Dan Alan, Sprague, David Michael, Miller, Paul Andrew, Ravishankar, Venkataramaiah
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): Tsegaye, Saba
• Application Number:
  US09/205,809
• Time in Patent Office: 1,089 Days
• Field of Search: 370/382, 370/353, 370/354, 370/401, 370/410, 370/460, 370/467, 370/469, 370/522, 370/524, 370/465, 370/466, 370/426, 379/115, 379/205, 379/220, 379/228, 379/230
• US Class Current: 370/467
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 69/085 specially adapted for interworking of IP-based networks with other networks
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/169 Special adaptations of TCP, UDP or IP for interworking of IP based networks with other networks protocols for interworking, protocol conversion H04L69/08
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04Q 3/0025 Provisions for signalling
• CPC Class Codes: H04Q 3/0029 Provisions for intelligent networking
• CPC Class Codes: H04Q 3/0045 involving hybrid, i.e. a mixture of public and private, or multi-vendor systems

Abstract

Seamless transport of messages is provided between SS7 network elements and Internet Protocol (IP) network elements using an STP as an intermediary. Thus, messages may be routed between a first SP and a second SP via an STP using IP. Messages may be routed between an SP and an IP node via an STP using IP. Messages also may be routed between a first IP node and a second IP node via an STP using IP. Thus, the STP can be used as a vehicle for message transport among nodes of an SS7 network, among nodes of an IP network and between SS7 and IP networks. SS7 messages are bidirectionally communicated between an STP and at least one other SP of an SS7 network using IP, preferably TCP/IP. Preferably, SS7 messages are bidirectionally communicated between an STP and at least one SCP using IP. In particular, a first SS7 message that is received from the STP includes an SS7 Message Transfer Part (MTP) layer, an SS7 Signaling Connection Control Part (SCCP) layer and an SS7 Transaction Capability Application Part (TCAP) layer. The MTP layer (SS7 levels 1-3) is stripped from the first SS7 message. An IP routing layer is added to the SSCP layer and the TCAP layer that remain in the first SS7 message, to create a first IP message. The IP routing layer includes an IP address. The first IP message is transmitted to the IP address over an IP network. A second IP message is received from the IP network. The second IP message includes an SS7 SCCP layer, an SS7 TCAP layer and an IP routing layer. The IP routing layer is stripped from the second IP message to create a second SS7 message including an SS7 SCCP layer and an SS7 TCAP layer. The second SS7 message is then transferred to the STP.

Claims

1. A Signaling Point (SP) for a Signaling System 7 (SS7) network, the SP comprising:

(a) a Signal Transfer Point (STP) that transfers SS7 call signaling messages between other SPs of the SS7 network; and

(b) an SS7/Internet Protocol (IP) gateway that is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and at least one of the other SPs of the SS7 network using Internet Protocol (IP), wherein the SS7/IP gateway comprises;

(b)(i) an interprocessor message transport (IMT) bus;

(b)(ii) a plurality of link interface modules (LIMs) that are connected to the IMT bus, each of the LIMs being connected to at least one of the other SPs of the SS7 network, the LIMs communicating with one another via the IMT bus to transfer the SS7 call signaling messages among the at least one of the other SPs of the SS7 network; and

(b)(iii) a data communications module (DCM) that is connected to the IMT bus and to an IP network, to map the SS7 call signaling messages between SS7 and IP and thereby bidirectionally transfer the SS7 call signaling messages between the STP and the at least one of the other SPs of the SS7 network using IP, wherein the DCM is not connected to the LIMs via an external SS7 signaling link.

2. The SP according to claim 1 wherein the DCM comprises:

(a) means for receiving from the IMT bus, a first SS7 call signaling message including an SS7 Message Transfer Part (MTP) level, an SS7 Signaling Connection Control Part (SCCP) level and an SS7 Transaction capabilities Application Part (TCAP) level;

(b) means for stripping the MTP level from the first SS7 call signaling message;

(c) means for adding an IP network layer to the SCCP level and the TCAP level that remain in the first SS7 call signaling message to create a first IP message, the IP network layer including an IP address;

(d) means for transmitting the first IP message to the IP address over the IP network;

(e) means for receiving a second IP message from the IP network, the second IP message including an SS7 SCCP level, an SS7 TCAP level and an IP network layer;

(f) means for stripping the IP network layer from the second IP message to create a second SS7 call signaling message including an SS7 SCCP level and an SS7 TCAP level; and

(g) means for transferring the second SS7 call signaling message to the IMT bus.

3. The SP according to claim 1 wherein the DCM comprises:

(a) means for receiving from the IMT bus, a first SS7 call signaling message including an SS7 Message Transfer Part (MTP) level, an SS7 Signaling Connection Control Part (SCCP) level and an SS7 Transaction Capability Application Part (TCAP) level;

(b) means for stripping the MTP level from the first SS7 call signaling message;

(c) means for placing the SCCP level and the TCAP level that remain in the first SS7 call signaling message in a Transmission Control Protocol (TCP) transport layer to create a first TCP message;

(d) means for adding an IP network layer to the first TCP message to create a first TCP/IP message, the IP network layer including an IP address;

(e) means for transmitting the first TCP/IP message to the IP address over the IP network using TCP transport;

p1 (f) means for receiving a second TCP/IP message from the IP network, the second TCP/IP message including an SS7 SCCP level and an SS7 TCAP level in a TCP transport layer and an IP network layer;

(g) means for stripping the IP network layer from the second IP message to create a second TCP transport message including the SS7 SCCP level and the SS7 TCAP level;

(h) means from removing the TCP transport layer from the second TCP message to create a second SS7 call signaling message including an SS7 SCCP level and an SS7 TCAP level; and

(i) means for transferring the second SS7 call signaling message to the IMT bus.

4. The SP according to claim 1 wherein the DCM comprises:

(a) an IP converter that is responsive to the IMT bus, to map an SS7 call signaling message into IP, and that is responsive to the IP network to map an IP message into SS7;

(b) a Message Handling Discrimination (HMDC) function that is responsive to the IP converter to determine whether an SS7 call signaling message that is received from the IP converter is destined for the SP or for one of the other SPs of the SS7 network; and

(c) a Message Handling Routing (HMRT) function that is responsive to the HMDC function, to route an SS7 call signaling message that is received from the IP converter to one of the other SPs of the SS7 network via the IMT bus.

5. An SP according to claim 1 wherein the SS7/IP gateway is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and at least one Service Control Point (SCP) using IP.

6. The SP according to claim 1 wherein the SS7/IP gateway is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and at least one Service Switching Point (SSP) using IP.

7. The SP according to claim 1 wherein the SS7/IP gateway is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and at least a second STP using IP.

8. The SP according to claim 1 wherein the SS7/IP gateway is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and a second mated STP using IP.

9. The SP according to claim 1 wherein the SS7/IP gateway is connected to the STP to bidirectionally communicate at least some of the transferred SS7 call signaling messages between the STP and other components of the SS7 network using Transmission Control Protocol/Internet Protocol (TCP/IP).

10. A Signal Transfer Point (STP) comprising a special-purpose SS7 signaling point for routing SS7 messages between other SS7 signaling points of the SS7 network, the STP comprising:

(a) means for bidirectionally transferring SS7 call signaling messages among Signaling Points (SP) of the SS7 network and Internet Protocol (IP) nodes of an IP network, wherein the means for bidirectionally transferring SS7 call signaling messages among SPs of the SS7 network and IP nodes of the IP network comprises;

(a)(i) an interprocessor message transport (IMT) bus; and

(a)(ii) a plurality of link interface modules (LIMs) that are connected to the IMT bus, each of the LIMs being connectable to at least one of the other SPs of the SS7 network, the LIMs communicating with one another via the IMT bus to transfer the SS7 call signaling messages among the at least one of the other SPs of the SS7network; and

(a)(ii) means for bidirectionally transferring messages among IP nodes of the IP network, wherein the means for bidirectionally transferring messages among IP nodes of the IP network includes a data communications module adapted to receive an IP-encapsulated SS7 call signaling message from a first IP node of the IP network and to route the IP-encapsulated SS7 call signaling message to a second IP node of the IP network, wherein the means for bidirectionally transferring SS7 call signaling messages is not coupled to the means for bidirectionally transferring messages among IP nodes via an external SS7 signaling link.

11. The STP according to claim 10 wherein the means for bidirectionally transferring SS7 call signaling messages among SPs of the SS7 network and IP nodes of the IP network comprises means for bidrectionally transferring SS7 call signaling messages between the STP and at least one Service Control Point (SCP) of the SS7 network.

12. The STP according to claim 10:

(a) wherein the means for bidirectionally transferring SS7 call signaling messages between SPs of the SS7 network and IP nodes of an IP network comprises means for bidirectionally transferring SS7 call signaling messages among SPs of the SS7 network using Transmission Control Protocol/lnternet Protocol (TCP/IP); and

(b) wherein the means for bidirectionally transferring messages among IP nodes of the IP network comprises means for bidirectionally transferring messages among IP nodes of the IP network using TCP/IP.

13. A Sign Transfer Point (STP) STP comprising a special-purpose SS7 signaling point for routing SS7 messages between other SS7 signaling points of the SS7 network, the STP including Signaling System Seven (SS7) and Internet Protocol (IP) communication capabilities, the STP comprising:

(a) an SS7 link interface module for receiving the first SS7 call signaling messages from first SS7 signaling points (SPs) in an SS7 network and for transmitting second SS7 call signaling messages to the first SS7 SPs via the SS7 network;

(b) a data communication module to receiving first IP-encapsulated SS7 call signaling messages from an IP network, formulating the second SS7 call signaling messages based on the first IP-encapsulated SS7 call signaling messages to the SS7 link interface module to be transmitted to the first SS7 SPs over the SS7 network, wherein the SS7 link interface module is not connected to the data communication module via an external SS7 signaling link; and

(c) an interprocessor message transfer (IMT) bus for connecting the SS7 link interface module and the data communications module within the STP.

14. The Signal Transfer Point of claim 13 wherein the first interface module is adapted to forward at least some of the first SS7 call signaling messages to the second interface module to be transmitted to second SS7 SPs over the IP network.

15. The Signal Transfer Point of claim 14 wherein the second interface module is adapted to formulate second IP-encapsulated SS7 call signaling messages based on the first SS7 call signaling messages received from the first interface module and to forward the second IP-encapsulated SS7 messages to the second SS7 SPs via the IP network.

16. The Signal Transfer Point of claim 15 wherein the second interface module is adapted to strip at least some SS7 level 1 and 2 information from the first SS7 call signaling messages received from the first interface module in formulating the second IP-encapsulated SS7 call signaling messages.

17. The Signal Transfer Point of claim 15 wherein the second interface module is adapted to retain SS7 level 1 and 2 information in the first SS7 call signaling messages received from the first interface module in formulating the second IP-encapsulated SS7 call signaling messages.

18. The Signal Transfer Point of claim 15 wherein the link interface module includes:

(a) a message handling a discrimination process for determining whether the first SS7 call signaling messages are intended for the STP or for other nodes in the SS7 network; and

(b) a message handling and distribution process for receiving the first SS7 call signaling messages from the message handling and discrimination process that are intended for the STP and forwarding the messages to a processing module within the STP for further processing.

19. The Signal Transfer Point of claim 18 wherein the message handling and distribution process is adapted to forward at least some of the first SS7 call signaling messages received from the message handling and discrimination process to the data communications module for IP processing.

20. The Signal Transfer Point of claim 13 wherein the data communications module includes an IP converter for receiving the first IP-encapsulated SS7 call signaling messages and formulating the second SS7 call signaling messages based on the first IP-encapsulated SS7 call signaling messages.

21. The Signal Transfer Point of claim 20 wherein the IP converter is adapted to remove IP header information from the first IP-encapsulated SS7 call signaling messages in formulating the second SS7 call signaling messages.

22. The Signal Transfer Point of claim 20 wherein the IP converter is adapted to remove Transmission Control Protocol (TCD) header information from the first IP-encapsulated SS7 messages in formulating the second SS7 call signaling messages.

23. The Signal Transfer Point of claim 20 wherein the IP converter is adapted to formulate second IP-encapsulated SS7 call signaling messages based on the first SS7 call signaling messages received from the link interface module and to forward the second IP-encapsulated SS7 call signaling messages to the second SS7 SPs via the IP network.

24. The Signal Transfer Point of claim 20 wherein the IP converter is adapted to strip at least some SS7 level 1 and 2 information from the first SS7 call signaling messages received from the link interface module in formulating the second IP-encapsulated SS7 messages.

25. The Signal Transfer Point of claim 20 wherein the IP converter is adapted to retain SS7 level 1 and 2 information in the first SS7 call signaling messages received from the link interface module in formulating the second IP-encapsulated SS7 call signaling messages.

26. The Signal Transfer Point of claim 13 wherein the first IP-encapsulated SS7 call signaling messages comprise IP-encapsulated Transaction Capabilities Application Part (TCAP) messages.

27. The Signal Transfer Point of claim 13 wherein the first SS7 call signaling messages comprise Transaction Capabilities Application Part (TCAP) messages and the second interface module is adapted to formulate second IP-encapsulated SS7 call signaling messages based on the TCAP messages.

28. The Signal Transfer Point of claim 27 wherein the second interface module is adapted to strip SS7 level 1 and 2 information from the TCAP messages in formulating the second IP-encapsulated SS7 call signaling messages.

29. The Signal Transfer Point of claim 27 wherein the data communications module is adapted to retain SS7 level 1 and 2 information in the TCAP messages in formulating the second IP-encapsulated SS7 call signaling messages.

30. The Signal Transfer Point of claim 13 comprising a processing module for receiving at least some of the second SS7 call signaling messages from the data communications module, performing global title translation on the second SS7 call signaling messages, and forwarding the global-title-translated messages to the link interface module to be transmitted to the first SS7 SPs over the SS7 network.

31. The Signal Transfer Point of claim 13 wherein the data communications module is adapted to formulate IP messages based on the first IP-encapsulated SS7 call signaling messages, and to forward the IP messages to IP nodes over the IP network.

32. The Signal Transfer point of claim 31 wherein the IP messages comprise IP-encapsulated SS7 call signaling messages.