Methods and apparatus for integrating signaling system number 7 networks with networks using multi-protocol label switching

• US 6,611,532 B1
• Filed: 12/07/1999
• Issued: 08/26/2003
• Est. Priority Date: 12/07/1999
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Sultana, Shabnam, Madour, Lila
• Primary Examiner(s): Ngo, Ricky
• Assistant Examiner(s): HA, YVONNE QUY M
• Application Number:
  US09/454,589
• Time in Patent Office: 1,358 Days
• Field of Search: 370/352-356, 370/400-401, 370/389, 370/386, 370/392, 370/397, 370/399, 370/384, 370/385, 370/373, 370/465, 370/466, 370/467, 370/410, 370/409, 379/229, 379/219, 709/249, 709/250
• US Class Current: 370/466
• CPC Class Codes: H04Q 3/0045 involving hybrid, i.e. a mixture of public and private, or multi-vendor systems
• CPC Class Codes: H04Q 3/66 Traffic distributors

Abstract

Techniques for implementing Multi-Protocol Label Switching (MPLS) directly in an SS7 protocol stack enable SS7 network layer protocols to interface, via MPLS, with literally any link layer technology. As a result, label switching can be used seamlessly throughout a collection of heterogeneous networks, including both IP-based and SS7-based networks. An exemplary method of routing SS7 data packets through a heterogeneous packet-switching network using MPLS includes the steps of: establishing an MPLS forwarding equivalence class (FEC), at least one element of the FEC being an SS7 destination; associating a label with the FEC at a first router in the heterogeneous packet switching network; attaching the label, at the first router, to a data packet belonging to the FEC; and forwarding the labeled data packet from the first router to a second router in the communications network. The SS7 destination can be, for example, a Destination Point Code (DPC), a Signaling Connection Control Part (SCCP) global title, or an SCCP subsystem number (SSN).

Claims

1. A method of routing Signaling System Number 7 (SS7) data packets through a heterogeneous packet-switching network using Multi-Protocol Label Switching (MPLS), comprising the steps of:

establishing an MPLS forwarding equivalence class (FEC), at least one element of the FEC being an SS7 destination;

associating a label with the FEC at a first router in the heterogeneous packet switching network;

attaching the label, at the first router, to a data packet belonging to the FEC; and

forwarding the labeled data packet from the first router to a second router in the communications network.

2. A method according to claim 1, wherein the SS7 destination is a Destination Point Code (DPC).

3. A method according to claim 1, wherein the SS7 destination is Signaling Connection Control Part (SCCP) global title.

4. A method according to claim 1, wherein the SS7 destination is an SCCP subsystem number (SSN).

5. A method according to claim 1, wherein the FEC includes a plurality of FEC elements selected from the group of DPC, global title, SSN, SS7 Country Code and SS7 National code.

6. A method according to claim 1, further comprising the step of advertising the label associated with the FIEC at the first router to other routers in the communications network.

7. A method according to claim 6, wherein the label association is advertised via a label distribution protocol (LDP).

8. A method according to claim 6, wherein each of a number of intermediary routers in a communications path of the data packet associates a label with the FEC of the data packet, and wherein each intermediary router in the path re-labels the data packet when forwarding the data packet to a next router.

9. A method according to claim 1, wherein the first router maintains a label information table including a plurality of FECs and associated labels, wherein a number of the FECs include SS7-based elements and another number of FECs Include non-SS7-based elements, and wherein the first router can serve as a destination for both SS7 data packets and non-SS7 data packets.

10. A method according to claim 9, wherein the label information table includes an internal identifier for each FEC, the internal identifier indicating which of a number of network layer (layer 3) protocols is used to convey data packets belonging to each FEC.

11. A Multi-Protocol Label Switching (MPLS) router for use in a heterogeneous packet switching communications network having at least one Internet Protocol (IP)-based portion and at least one Signaling System Number 7 (SS7)-based portion, said MPLS router comprising:

a routing table that stores information relating to an MPLS forwarding equivalence class (FEC), wherein an element of the FEC is a Signaling System Number 7 (SS7) destination; and

a label switching protocol processor that associates a label with the FEC, attaches the label to a data packet belonging to the FEC, and forwards the labeled data packet to another router in the communications network;

whereby MPLS routing techniques are utilized seamlessly throughout the IP-based portions and SS7-based portions of the network.

12. A router according to claim 11, wherein an element of the FEC is an SS7 Destination Point Code (DPC).

13. A router according to claim 11, wherein an element of the FEC is a, Signaling Connection Control Part (SCCP) global title.

14. A router according to claim 11, wherein an element of the FEC is an SCCP subsystem number (SSN).

15. A router according to claim 11, wherein the FEC includes a plurality of FEC elements selected from the group of DPC, global title, SSN, SS7 Country Code and SS7 National code.

16. A router according to claim 11, further comprising a label distribution processor configured to advertise the label associated with the FEC to other routers In the communications network.

17. A router according to claim 16, wherein the label distribution processor advertises labels via a label distribution protocol (LDP).

18. A router according to claim 11, wherein each of a number of intermediary routers in a communications path of the data packet associates a label with the FEC of the data packet, and wherein each intermediary router in the path re-labels the data packet when forwarding the data packet to a next router.

19. A router according to claim 11, wherein the routing table includes a plurality of FECs and associated labels, wherein a number of the FECs include SS7-based elements and another number of FECs include non-SS7-ased elements, and wherein the router can serve as a destination for both SS7 data packets and non-SS7 data packets.

20. A router according to claim 19, wherein the routing table includes an internal identifier for each FEC, the internal identifier indicating which of a number of network layer (layer 3) protocols Is used to convey data packets belonging to each FEC.