Point code emulation for common channel signaling system No. 7 signaling network

• US 8,452,890 B2
• Filed: 12/14/2007
• Issued: 05/28/2013
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: Ribbon Communications Operating Company, Inc. (Ribbon Communications, Inc.)
• Original Assignee: Performance Technologies Incorporated (Ribbon Communications, Inc.)
• Inventors: Glaude, Normand, Wesley-James, Charles, Aubry, Christine
• Primary Examiner(s): WINDER, PATRICE L
• Application Number:
  US12/528,652
• Publication Number:
  US 20100100597A1
• Time in Patent Office: 1,992 Days
• Field of Search: 709/230, 709/236, 709/237
• US Class Current: 709/236
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 49/3009 Header conversion, routing tables or routing tags
• CPC Class Codes: H04Q 3/0025 Provisions for signalling
• CPC Class Codes: H04Q 3/0029 Provisions for intelligent networking
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services

Abstract

The present invention relates to a point code emulation apparatus and method for dividing a Common Channel Signaling System No. 7 (or SS 7) signaling network into two or more networks. The point code emulator is adapted to receive TCAP messages from two or more subnets and converts, for the messages crossing over the subnets, the information of the TCAP messages, including originating point code, destination point code, and transaction identifier, (and optionally, calling party number and called party number), and forwards to the other one of the two or more subnets. Correspondence among the two or more subnets may be provisioned by an authorized user of the system, may be learned automatically by the system based on ISUP message correspondences or previous TCAP transactions, or may be automatically discovered by the system broadcasting messages to nodes in the destined one of the two or more subnets.

Claims

1. A method of routing a Transaction Capabilities Application Part (TCAP) message at a node for dividing a Signaling System No. 7 (SS7) signaling network into two or more subnets, comprising the steps of:

receiving said TCAP message from one of said two or more subnets;

extracting an originating point code (OPC), destination point code (DPC) and transaction identifier (TID) of said TCAP message;

looking up and retrieving, from a plurality of structured data storages a corresponding OPC, a corresponding DPC and a corresponding TID at the node for the other one of said two or more subnets based, partially or combinedly, on said OPC, said DPC and said TID of said received TCAP message;

replacing said OPC, said DPC, and said TID of said received TCAP message with said corresponding OPC, said corresponding DPC and said corresponding TID; and

forwarding said TCAP message with said corresponding OPC, said corresponding DPC and said corresponding TID to the other one of said two or more subnets.

2. The method as recited in claim 1, wherein said one of said two or more subnets is one of a public network and a private network.

3. The method as recited in claim 1, wherein said plurality of structured data storages comprises global title translation (GTT) databases and at least two hash tables wherein a first one of said at least two hash tables is for retrieving an existing record during a conversation and a second one of said at least two hash tables is for correlating bi-directional TCAP messages between TID records of the one of said two or more subnets and ones of the other one of said two or more subnets.

4. The method as recited in claim 1 further comprising a method for discovering said corresponding OPC, said corresponding DPC and said corresponding TID for said OPC, said DPC and said TID, said method comprising the steps of:

prior to receiving said TCAP message, receiving an ISDN User Part (ISUP) message from said one of said two or more subnets, wherein said ISUP message is, then, transferred and forwarded to said the other one of said two or more subnets;

extracting a first calling number and a first called number from said ISUP messages for recording said corresponding OPC and said corresponding DPC; and

recording the first calling number, the first called number, said corresponding OPC and said corresponding DPC in said plurality of structured data storages,

upon receiving said TCAP message, extracting a second calling number and a second called number from said TCAP, and looking up and retrieving said corresponding OPC, said corresponding DPC and said corresponding TID for the other one of said two or more subnets based, partially or combinedly, on the second calling number or the second called number from said plurality of said structured data storages.

5. The method as recited in claim 4, wherein said ISUP message is Initial Address Message (IAM) message.

6. The method as recited in claim 1 further comprising a method for discovering said corresponding OPC, said corresponding DPC and said corresponding TID, wherein said method comprising the steps of:

upon receiving said TCAP message from said one of said two or more subnets, broadcasting TCAP messages to all nodes of said the other one of said two or more subnets;

receiving at least one positive TCAP response from said the other one of said two or more subnets;

selecting a most successful one of said at least one positive TCAP response, and extracting OPC, DPC and TID of said the most successful one of said at least one TCAP response;

recording, in at least one of said plurality of structured data storages, that said OPC, said DPC and said TID of said TCAP message from said one of said two or more subnets corresponds to said OPC, said DPC and said TID of said the most successful one of said at least one positive TCAP response as said corresponding OPC, said corresponding DPC and said corresponding TID for said the other one of said two or more subnets.

7. A non-transitory computer readable storage medium storing executable computer program instructions which,

when executed at a node, cause the node to perform a process of routing a

Transaction Capabilities Application Part (TCAP) message between two or more subnets of a SS7 signaling network, comprising steps of:

receiving said TCAP message at the node from one of said two or more subnets;

at the node, extracting originating point code (OPC), destination point code (DPC) and transaction identifier (TID) of said TCAP message;

looking up and retrieving, from a plurality of structured data storages, a corresponding OPC, a corresponding DPC and a corresponding TJD for the other one of said two or more subnets based, partially or combinedly, on said OPC, said DPC and said TID of said received TCAP message;

at the node, replacing said OPC, said DPC, and said TID of said received TCAP message with said corresponding OPC, said corresponding DPC and said corresponding TID; and

forwarding said TCAP message from the node with said corresponding OPC said corresponding DPC and said corresponding TID to the other one of said two or more subnets.

8. The non-transitory computer readable storage medium as recited in claim 7, wherein said one of said two or more subnets is one of a public network and a private network.

9. The non-transitory computer readable storage medium as recited in claim 7, wherein said plurality of structured data storages comprises global title translation (GTT) databases and at least two hash tables wherein a first one of said at least two hash tables is for retrieving an existing record during a conversation and a second one of said at least two hash tables is for correlating bi-directional TCAP messages between TID records of the one of said two or more subnets and ones of the other one of said two or more subnets.

10. The non-transitory computer readable storage medium as recited in claim 9 further comprises a method for discovering said corresponding OPC, said corresponding DPC and said corresponding TID for said OPC, said DPC and said TID, said method comprising the steps of:

prior to receiving said TCAP message, receiving an ISDN User Part (ISUP) message from said one of said two or more subnets, wherein said ISUP message is, then, transferred and forwarded to said the other one of said two or more subnets;

extracting a first calling number and a first called number from said ISUP messages for recording said corresponding OPC and said corresponding DPC; and

recording the first calling number, the first called number, said corresponding OPC and said corresponding DPC in said plurality of said structured data storage;

upon receiving said TCAP message, extracting a second calling number and a second called number from said TCAP, and looking up and retrieving said corresponding OPC, said corresponding DPC and said corresponding TID for the other one of said two or more subnets based, partially or combinedly, on the second calling number or the second called number from said plurality of said structured data storages.

11. The non-transitory computer readable storage medium as recited in claim 10, wherein said ISUP message is Initial Address Message (IAM) message.

12. The non-transitory computer readable storage medium as recited in claim 9 further comprises a method for discovering said corresponding OPC, said corresponding DPC and said corresponding TID, wherein said method comprising the steps of:

broadcasting messages to all nodes of said the other one of said two or more subnets;

receiving at least one positive response from said the other one of said two or more subnets;

selecting a most successful one of said at least one positive response, and extracting OPC, DPC and TID of said the most successful one of said at least one response;

recording, in said plurality of structured data storages, that said OPC, said DPC and said TID of said TCAP message corresponds to said OPC, said DPC and said TID of said the most successful one of said at least one message as said corresponding OPC, said corresponding DPC and said corresponding TID for said the other one of said two or more subnets.

13. A node for routing a

Transaction Capabilities Application Part (TCAP) message between at least two

subnets of a SS7 signaling network, the node comprising:

a corresponding number of interfaces to said at least two subnets of said Signaling System No. 7 (SS7) signaling network for interfacing with said at least two subnets;

a plurality of structured data storages;

a processor in communication with said corresponding number of said interfaces and said plurality of data storages, wherein said processor carries out a process of said routing said TCAP message between said at least two subnets, said process comprising the steps of;

receiving said TCAP message from one of said two or more subnets;

extracting originating point code (OPC), destination point code (DPC) and transaction identifier (TID) of said TCAP message;

looking up and retrieving, from said plurality of structured data storages, a corresponding OPC, a corresponding DPC and a corresponding T-D for the other one of said two or more subnets based, partially or combinedly, on said OPC, said DPC and said TID of said received TCAP message;

replacing said OPC, said DPC, and said TID of said received TCAP message with said corresponding OPC, said corresponding DPC and said corresponding TID; and

forwarding said TCAP message with said corresponding OPC, said corresponding DPC and said corresponding TID to the other one of said two or more subnets.

14. The network apparatus as recited in claim 13, wherein said one of said two or more subnets is a public network or a private network.

15. The network apparatus as recited in claim 13, wherein said plurality of structured data storages comprises global title translation (GTT) databases and at least two hash tables wherein a first one of said at least two hash tables is for retrieving an existing record during a conversation and a second one of said at least two hash tables is for correlating bi-directional TCAP messages between TID records of the one of said two or more subnets and ones of the other one of said two or more subnets.

16. The network apparatus as recited in claim 13 wherein said processor further discovers said corresponding OPC, said corresponding DPC and said corresponding TID for said OPC, said DPC and said TID by carrying out a method comprising the steps of:

prior to receiving said TCAP message, receiving an ISDN User Part (ISUP) message from said one of said two or more subnets, wherein said ISUP message is, then, transferred and forwarded to said the other one of said two or more subnets;

extracting a first calling number and a first called number from said ISUP message for recording said corresponding OPC and said corresponding DPC; and

recording the first calling number, the first called number, said corresponding OPC and said corresponding DPC in said plurality of said structured data storages,

upon receiving said TCAP message, extracting a second calling number and a second called number from said TCAP, and looking up and retrieving said corresponding OPC, said corresponding DPC and said corresponding TID for the other one of said two or more subnets based, partially or combinedly, on the second calling number or the second called number from said plurality of said structured data storages.

17. The network apparatus as recited in claim 16, wherein said ISUP message is an Initial Address Message (IAM) message.

18. The network apparatus as recited in claim 13 wherein said processor discovers said corresponding OPC, said corresponding DPC and said corresponding TID by carrying out the method comprising the steps of:

upon receiving said TCAP message from said one of said two or more subnets, broadcasting TCAP messages to all nodes of said the other one of said two or more subnets;

receiving at least one positive TCAP response from said the other one of said two or more subnets;

selecting a most successful one of said at least one positive TCAP response, and extracting OPC, DPC and TID of said the most successful one of said at least one TCAP response;

recording, in at least one of said plurality of structured data storages, that said OPC, said DPC and said TID of said TCAP message from said one of said two or more subnets corresponds to said OPC, said DPC and said TID of said the most successful one of said at least one positive TCAP response as said corresponding OPC, said corresponding DPC and said corresponding TID for said the other one of said two or more subnets.