Bridging and signalling subsystems and methods for private and hybrid communications systems including multimedia systems

• US 6,587,460 B1
• Filed: 02/28/2000
• Issued: 07/01/2003
• Est. Priority Date: 03/03/1995
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Bell, Robert T., Platt, Richard J.
• Primary Examiner(s): TON, DANG T
• Application Number:
  US09/514,557
• Time in Patent Office: 1,219 Days
• Field of Search: 370/216, 370/219, 370/220, 370/226.1, 370/227, 370/228, 370/247, 370/248, 370/251, 370/256, 370/257, 370/351, 370/400, 370/401, 370/404, 370/406, 370/408, 370/431, 370/908, 370/901, 370/254, 370/469, 370/522, 370/496, 370/395.1, 370/471, 370/385, 340/827, 340/825.05, 340/825.02, 340/825.5, 340/825.51, 379/202
• US Class Current: 370/385
• CPC Class Codes: H04L 12/413 with random access, e.g. carrier-sense multiple-access with collision detection [CSMA-CD]
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 7/1245 where a network other than PSTN/ISDN interconnects two PSTN/ISDN networks
• CPC Class Codes: H04Q 11/0457 Connection protocols
• CPC Class Codes: H04Q 2213/13107 Control equipment for a part of the connection, distributed control, co-processing
• CPC Class Codes: H04Q 2213/13166 Fault prevention
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/13176 Common channel signaling, CCS7
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13209 ISDN
• CPC Class Codes: H04Q 2213/13215 Code checking, CRC
• CPC Class Codes: H04Q 2213/13216 Code signals, frame structure
• CPC Class Codes: H04Q 2213/13248 Multimedia
• CPC Class Codes: H04Q 2213/1329 Asynchronous transfer mode, ATM
• CPC Class Codes: H04Q 2213/13337 Picturephone, videotelephony
• CPC Class Codes: H04Q 2213/13389 LAN, internet
• CPC Class Codes: H04Q 2213/13396 Signaling in general, in-band signalling

Abstract

A subsystem for communicating a private network signalling message over a packet network and bridges for communicating a Media Access Control (MAC) layer frame over an isochronous channel and for communicating an isochronous signalling frame over a nonisochronous network. The subsystem comprises: (1) an encapsulation circuit, coupled to a transmitting user station, capable of receiving the private network signalling message from the transmitting user station, the encapsulating circuit encapsulating the signalling message within, and adding source and destination addresses to, a routable protocol frame, the source and destination addresses corresponding to addresses of the transmitting user station and a particular receiving user station, the encapsulation circuit queuing the routable protocol frame for transmission over the packet network and (2) a de-encapsulation circuit, coupled to the particular receiving user station, capable of receiving the routable protocol frame, the de-encapsulation circuit extracting the signalling message from the routable protocol frame, the packet network thereby simulating a point-to-point connection between the transmitting and particular receiving user stations to effect node-to-node private network signalling therebetween.

Claims

1. An apparatus for communicating nonisochronous data over an isochronous channel, comprising:

a reception module coupled to a nonisochronous network, the reception module operable to receive the nonisochronous data from the nonisochronous network; and

an encapsulation module coupled to the reception module and the isochronous channel, the encapsulation module operable to;

divide the stored nonisochronous data into first and second segments;

encapsulate the first and second segments into a first frame and a second frame, respectively; and

queue the first and second frames for transmission over the isochronous channel.

2. The apparatus of claim 1, wherein the reception module comprises a buffer operable to store the nonisochronous data received from the nonisochronous network.

3. The apparatus of claim 1, wherein the first frame comprises an address field and a control field.

4. The apparatus of claim 1, wherein the encapsulation module is further operable to negotiate a larger maximum frame size by generating and receiving transmit identification (XID) messages over the isochronous channel.

5. The apparatus of claim 1, wherein the encapsulation module is further operable to receive a second frame from the isochronous channel and to de-encapsulate the second frame to form nonisochronous data for transmission over the nonisochronous network.

6. The apparatus of claim 1, wherein the nonisochronous data comprises a network layer packet.

7. The apparatus of claim 1, wherein the nonisochronous data comprises a Media Access Control (MAC) layer frame.

8. A method of communicating nonisochronous data over an isochronous channel, comprising:

receiving nonisochronous data from a nonisochronous network;

dividing the nonisochronous data into first and second segments;

encapsulating the first and second segments into a first frame and a second frame, respectively; and

queuing the first and second frames for transmission over the isochronous channel.

9. The method of claim 8, further comprising storing the nonisochronous data in a buffer prior to encapsulating the nonisochronous data.

10. The method of claim 8, wherein the first frame comprises an address field and a control field.

11. The method of claim 8, further comprising negotiating a larger maximum frame size by generating and receiving transmit identification (XID) messages over the isochronous channel.

12. The method of claim 8, further comprising receiving a second frame from the isochronous channel and de-encapsulating the second frame to form nonisochronous data for transmission over the nonisochronous network.

13. The method of claim 8, wherein the nonisochronous data comprises a network layer packet.

14. The method of claim 8, wherein the nonisochronous data comprises a Media Access Control (MAC) layer frame.

15. A computer program for communicating nonisochronous data over an isochronous channel, the program encoded on a computer-readable medium and operable to execute the following steps:

receiving nonisochronous data from a nonisochronous network;

dividing the nonisochronous data into first and second segments;

encapsulating the first and second segments into a first frame and a second frame, respectively; and

queuing the first and second frames for transmission over the isochronous channel.

16. The computer program of claim 15, further operable to perform the step of storing the nonisochronous data in a buffer prior to the step of encapsulating the nonisochronous data.

17. The computer program of claim 15, wherein the first frame comprises an address field an a control field.

18. The computer program of claim 15, further operable to perform the following steps:

negotiating a larger maximum frame size by generating and receiving transmit identification (XID) messages over the isochronous channel; and

if the step of negotiating is unsuccessful, dividing the nonisochronous data into first and second segments, individually encapsulating the first and second segments into the first frame and a second frame, respectively, assigning a segment number to each of the first and second frames, and queuing the first and second frames for transmission over the isochronous channel.

19. The computer program of claim 15, further operable to perform the steps of receiving a second frame from the isochronous channel and de-encapsulating the second frame to form nonisochronous data for transmission over the nonisochronous network.

20. The computer program of claim 15, wherein the nonisochronous data comprises a network layer packet.

21. The computer program of claim 15, wherein the nonisochronous data comprises a Media Access Control (MAC) layer frame.

22. An apparatus for communicating an isochronous signalling frame over a nonisochronous network, comprising:

a reception module coupled to an isochronous channel and operable to receive the isochronous signalling frame from a source device via the isochronous channel; and

an encapsulation module coupled to the reception module and a nonisochronous network, the encapsulation module operable to encapsulate the isochronous signalling frame into a routable protocol frame and to queue the routable protocol frame for transmission over the nonisochronous network to a destination device, the nonisochronous network thereby capable of simulating a point-to-point connection between the source device and the destination device.

23. The apparatus of claim 22, wherein the routable protocol frame is a User Datagram Protocol/Internet Protocol (UDP/IP) frame, the encapsulation module further operable to associate a source address field of the routable protocol frame with a source address and to associate a destination address field of the routable protocol frame with an address of the destination device.

24. The apparatus of claim 22, wherein the encapsulation module is further operable to:

receive a subsequent routable protocol frame from the destination device via the nonisochronous network;

de-encapsulate an isochronous signalling frame from the subsequent routable protocol frame; and

queue the isochronous signalling frame for transmission over the isochronous channel.

25. The apparatus of claim 22, wherein the reception module is further operable to validate a frame check sequence number of the isochronous signalling frame.

26. The apparatus of claim 22, further comprising a storage module coupled to the reception module and operable to store the isochronous signalling frame.

27. The apparatus of claim 22, wherein the isochronous signalling frame comprises a Q.931 signalling frame.

28. The apparatus of claim 22, wherein the isochronous signalling frame comprises an SS7 signalling frame.

29. A method of communicating an isochronous signalling frame over a nonisochronous network, comprising:

receiving the isochronous signalling frame from a source device via an isochronous channel;

encapsulating the isochronous signalling frame into a routable protocol frame; and

queuing the routable protocol frame for transmission over the nonisochronous network to a destination device, the nonisochronous network thereby capable of simulating a point-to-point connection between the source device and the destination device.

30. The method of claim 29, wherein the routable protocol frame is a User Datagram Protocol/Internet Protocol (UDP/IP) frame and the step of encapsulating further comprises associating a source address field of the routable protocol frame with a source address and associating a destination address field of the routable protocol frame with an address of the destination device.

31. The method of claim 29, further comprising:

receiving a subsequent routable protocol frame from the destination device via the nonisochronous network;

de-encapsulating a subsequent isochronous signalling frame from the subsequent routable protocol frame; and

queuing the isochronous signalling frame for transmission over the isochronous channel.

32. The method of claim 29, wherein the step of receiving comprises validating a frame check sequence number of the isochronous signalling frame.

33. The method of claim 29, further comprising storing the isochronous signalling frame.

34. The method of claim 29, wherein the isochronous signalling frame comprises a Q.931 signalling frame.

35. The method of claim 29, wherein the isochronous signalling frame comprises an SS7 signalling frame.

36. A computer program for communicating an isochronous signalling frame over a nonisochronous network, the computer program encoded on a computer-readable medium and operable to execute the following steps:

receiving the isochronous signalling frame from a source device via an isochronous channel;

encapsulating the isochronous signalling frame into a routable protocol frame; and

queuing the routable protocol frame for transmission over the nonisochronous network to a destination device, the nonisochronous network thereby capable of simulating a point-to-point connection between the source device and the destination device.

37. The computer program of claim 36, wherein the routable protocol frame is a User Datagram Protocol/Internet Protocol (UDP/IP) frame and the step of encapsulating further comprises associating a source address field of the routable protocol frame with a source address of the routable protocol frame and associating a destination address field with an address of the destination device.

38. The computer program of claim 36, further comprising:

receiving a subsequent routable protocol frame from the destination device via the nonisochronous network;

de-encapsulating a subsequent isochronous signalling frame from the subsequent routable protocol frame; and

queuing the isochronous signalling frame for transmission over the isochronous channel.

39. The computer program of claim 36, wherein the step of receiving comprises validating a frame check sequence number of the isochronous signalling frame.

40. The computer program of claim 36, further comprising storing the isochronous signalling frame.

41. A subsystem for communicating a private network signalling message between a first node and a second node over a packet network, comprising:

an encapsulation module coupled to the first node associated with a transmitting user station, the encapsulation module operable to;

receive a private network signalling message from the first node;

associate the signalling message with a source address and a destination address, the source address corresponding to an address of the first node and the destination address corresponding to an address of the second node;

encapsulate the signalling message, the source address, and t he destination address into a routable protocol frame; and

queue the routable protocol frame for transmission over the packet network; and

a de-encapsulation module coupled to a second node associated with a receiving user station, the de-encapsulation module operable to;

receive the routable protocol frame; and

de-encapsulate the signalling message from the routable protocol frame, the packet network thereby simulating a point-to-point connection between the first node and the second node to effect node-to-node private network signalling therebetween.

42. The subsystem of claim 41, wherein the packet network comprises redundant backbones coupling the encapsulation module and the de-encapsulation module.

43. The subsystem of claim 41, wherein the transmitting user station is operable to create a user information path via an isochronous channel.

44. The subsystem of claim 41, wherein the second node is coupled to a second encapsulation module and the first node is coupled to a second de-encapsulation module, the second node thereby capable of transmitting a subsequent signalling message to the first node in response to receipt of the signalling message from the first node.

45. The subsystem of claim 41, wherein the encapsulation module and the de-encapsulation module each comprise sequences of executable software instructions.

46. A method of communicating a private network signalling message between a first node and a second node over a packet network, comprising:

receiving a private network signalling message from the first node associated with a transmitting user station;

associating the signalling message with a source address and a destination address, the source address corresponding to an address of the first node and the destination address corresponding to an address of the second node;

encapsulating the signalling message, the source address, and the destination address into a routable protocol frame;

queuing the routable protocol frame for transmission over the packet network;

receiving the routable protocol frame at a second node associated with a receiving user station; and

de-encapsulating the signalling message from the routable protocol frame, the packet network thereby simulating a point-to-point connection between the first node and the second node to effect node-to-node private network signalling therebetween.

47. The method of claim 46, wherein the packet network comprises redundant backbones coupling the encapsulation module and the de-encapsulation module.

48. The method of claim 46, further comprising creating a user information path via an isochronous channel.

49. The method of claim 46, further comprising transmitting a subsequent signalling message from the second node to the first node in response to receipt of the signalling message from the first node.

50. A computer program for communicating a private network signalling message between a first node and a second node over a packet network, the computer program operable to execute the following steps:

receiving a private network signalling message from the first node associated with a transmitting user station;

associating the signalling message with a source address and a destination address, the source address corresponding to an address of the first node and the destination address corresponding to an address of the second node;

encapsulating the signalling message, the source address, and the destination address into a routable protocol frame;

queuing the routable protocol frame for transmission over the packet network;

receiving the routable protocol frame at a second node associated with a receiving user station; and

de-encapsulating the signalling message from the routable protocol frame, the packet network thereby simulating a point-to-point connection between the first node and the second node to effect node-to-node private network signalling therebetween.

51. The computer program of claim 50, wherein the packet network comprises redundant backbones coupling the encapsulation module and the de-encapsulation module.

52. The computer program of claim 50, further comprising creating a user information path via an isochronous channel.

53. The computer program of claim 50, further comprising transmitting a subsequent signalling message from the second node to the first node in response to receipt of the signalling message from the first node.