Switched telecommunications network with bandwidth management for different types of multiplexed traffic

• US 5,638,363 A
• Filed: 07/27/1995
• Issued: 06/10/1997
• Est. Priority Date: 03/09/1994
• Status: Expired due to Term

• Current Assignee: British Telecommunications PLC (BT Group PLC)
• Original Assignee: British Telecommunications PLC (BT Group PLC)
• Inventors: Cox, Simon A., Gittins, Christopher J.
• Primary Examiner(s): Kizou, Hassan
• Application Number:
  US08/507,938
• Time in Patent Office: 684 Days
• Field of Search: 370/53, 370/58.1, 370/58.3, 370/68.1, 370/110.1, 370/112, 370/118, 379/219, 379/220, 379/225, 379/229, 375/240, 387/29, 358/400, 348/14, 348/16, 348/17
• US Class Current: 370/358
• CPC Class Codes: H04L 2012/5615 Network termination, e.g. NT1, NT2, PBX
• CPC Class Codes: H04L 2012/5619 Network Node Interface, e.g. tandem connections, transit switching
• CPC Class Codes: H04L 2012/5632 Bandwidth allocation
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/1322 PBX
• CPC Class Codes: H04Q 2213/13332 Broadband, CATV, dynamic bandwidth allocation
• CPC Class Codes: H04Q 2213/13337 Picturephone, videotelephony
• CPC Class Codes: H04Q 2213/13384 Inter-PBX traffic, PBX networks, e.g. corporate networks
• CPC Class Codes: H04Q 2213/13523 bandwidth management, e.g. capacity management
• CPC Class Codes: H04Q 3/0016 Arrangements providing connection between exchanges
• CPC Class Codes: H04Q 3/0029 Provisions for intelligent networking
• CPC Class Codes: H04Q 3/0066 Bandwidth allocation or management

Abstract

A switched telecommunications network includes different types of traffic, such as audio data, including voice data, fax and modem originated data, digital computer originated data and video data. A communications link connects a user'"'"'s site to the network, and a bandwidth manager is provided to multiplex traffic of different types for transmission over the link. After transmission over the link, a complementary bandwidth manager is arranged to de-multiplex the traffic for application to the respective switch. The bandwidth manager is arranged to dynamically allocate bandwidth to the different types of traffic, thereby optimizing the available bandwidth provided by the communications link.

Claims

1. A switched telecommunications network comprising:

a main network having a plurality of interconnected switching devices,

a first communications link connecting a user'"'"'s site to the main network via a first of the switching devices,

the first switching device including first switching means for switching a first type of traffic, and second switching means for switching a second type of traffic,

a bandwidth manager disposed at the user'"'"'s end of the first communications link which analyzes data to be transmitted and provides compression that is dependent on the type of data being transmitted,

the bandwidth manager being arranged to multiplex traffic of the first and second types for transmission over the link, and

a complementary bandwidth manager disposed at the switching end of the first communications link, the complementary bandwidth manager being arranged to de-multiplex the first and second traffic types for application to the first switching device;

a second communications link connecting a second user'"'"'s site to the main network via a second of the switching devices,

the second switching device including first switching means for switching a first type of traffic, and second switching means for switching a second type of traffic,

a bandwidth manager disposed at the user'"'"'s end of the second communications link,

the bandwidth manager of the second communications link reconstituting user originated signalling data.

2. A network as in claim 1, wherein:

the switching devices are configured for switching non-compressed data, and

means are provided for adding blank data to the compressed data so as to produce switchable words without decompressing the compressed data.

3. A network as in claim 2, further comprising means for removing the added blank data after switching and prior to re-transmission.

4. A network as in claim 1 wherein:

the bandwidth manager of the first communications link compresses user-originated signalling data and network signalling data is added to effect transmission, and

the bandwidth manager of the second communications link reconstitutes user-originated signalling data.

5. A network as in claim 1, wherein the bandwidth manager of the first communications link compresses voice data to a higher degree than non-voice data.

6. A network as in claim 5, wherein the bandwidth manager of the first communications link provides a compression ratio of voice data to non-voice data that is eight to one.

7. A network as in claim 6, wherein:

the bandwidth manager of the first communications link compresses 64-bit voice data words to 8-bit words for transmission along said link, and

the complementary bandwidth manager of the first communications link adds 56 additional null bits to each 8-bit compressed word to form a quasi 64-bit switchable word.

8. A network as in claim 1 wherein the bandwidth manager of the first communications link compresses data prior to being multiplexed for transmission to a local exchange.

9. A network as in claim 8, wherein the multiplexed data is demultiplexed at the local exchange, and each type of data obtained from the multiplex is supplied to respective networks in compressed form.

10. A network as in claim 1 wherein:

the first and second switching devices each comprises a third switching means for switching a third type of traffic,

the bandwidth manager of the first communications link is arranged to multiplex the first, second and third types of traffic, and

the complementary bandwidth manager of said link is arranged to de-multiplex the first, second and third types of traffic.

11. A network as in claim 10, wherein the first type of traffic is voice data or audio modulated data, the second type of traffic is computer-generated data and the third type of traffic is video data.

12. A network as in claim 1 wherein the bandwidth manager of the first communications link allocates bandwidth to particular types of traffic in response to customer demand.

13. A network as in claim 12, wherein the bandwidth manager of the first communications link includes means for guaranteeing a minimum level of bandwidth for particular traffic types.

14. A network as in claim 1 wherein the first type of traffic is voice data or audio modulated data, and the second type of traffic is computer-generated data.

15. A network as in claim 14 wherein the bandwidth manager of the first communications link includes means for identifying voice data, and for compressing the voice data to facilitate efficient transmission through the network.

16. A network as in claim 14 wherein the bandwidth manager of the first communications link includes means for identifying facsimile encoded data, and for re-coding the facsimile data to facilitate efficient transmission through the network.

17. A network as in claim 14 wherein the bandwidth manager of the first communications link includes means for identifying audio encoded computer originated data from a modem, and for re-coding said data to facilitate efficient transmission.

18. A network as in claim 1 wherein the bandwidth manager of the first communications link includes:

means for converting signalling data generated by a user into data which may be transmitted onto the main network via the first switching device, and

means for reconverting converted signalling data received from the main network into a form recognisable by the associated user.

19. A network as in claim 1 wherein the bandwidth manager of the first communications link includes means for interfacing a plurality of user'"'"'s lines.

20. A network as in claim 1 wherein the bandwidth manager of the first communications link includes means for detecting overflow conditions, and for establishing an overflow link to an alternative network.

21. A network as in claim 1 wherein the bandwidth manager of the first communications link includes means for supplying operational data to management control computers.

22. A method of communicating over a telecommunications network, the method comprising the steps of:

switching a first type of traffic via a first switching means,

switching a second type of traffic via a second switching means,

connecting a user'"'"'s site to the network via a communications link having a bandwidth manager which analyzes the traffic to be transmitted and which directs different types of traffic to a respectively corresponding one of said switching steps

multiplexing traffic of the first and second types for transmission over the link at the user'"'"'s end of the link, and

de-multiplexing the first and second traffic types for application to respective switching means at the switching end of the link and decompressing each type of traffic to reconstitute the original transmitted traffic.

23. A method as in claim 22, further comprising the step of allocating bandwidth to particular types of traffic in response to customer demand.

24. A method as in claim 23, further comprising the step of guaranteeing a minimum level of bandwidth for particular traffic types.

25. A method as in claim 24, further comprising the step of multiplexing a third traffic type for transmission over the link.

26. A method as in claim 22 wherein one of the traffic types is video data.

27. A method as in claim 22 wherein one of the said traffic types is computer originated data.

28. A method as in claim 22 wherein one of the traffic types is voice data or audio modulated data.

29. A method as in claim 28, further comprising the steps of:

identifying voice data, and

compressing the voice data to reduce transmission bandwidth requirements.

30. A method as in claim 28, further comprising the steps of:

identifying facsimile encoded data, and

recoding said facsimile data so as to facilitate efficient transmission.

31. A method as in claim 28, further comprising the steps of:

identifying audio encoded computer originated data from a modem, and

recoding said data to facilitate efficient transmission.

32. A method of transmitting data, via bandwidth managing devices, through a switched network constituted by a plurality of interconnected switching devices, the method comprising the steps of:

compressing user originated data at a transmitting bandwidth managing device,

transmitting the compressed data to a first complementary bandwidth managing device connected to a first switching device which analyzes the data to be transmitted and provides a level of compression that is dependent on the type of data being transmitted,

switching the compressed data through a plurality of switching devices,

transmitting the switched compressed data to a receiving bandwidth managing device via a second complementary bandwidth managing device connected to a second switching device, and

decompressing the compressed data at the receiving bandwidth managing device to reconstitute the originated data.

33. A method of communicating through a switched telecommunications network, the method comprising the steps of:

generating user specific signalling data,

converting said data to transmittable data at a bandwidth managing device which analyzes the data to be transmitted and provides a level of compression that is dependent on the type of data being transmitted,

supplying the transmittable data to a public switched network from the bandwidth managing device,

receiving the transmitted data at a receiving bandwidth managing device, and reconverting said user specific signalling data at the receiving bandwidth managing device to reconstitute the original user specific signalling data.

34. A bandwidth manager connectable between a transmission link and a switching device, the bandwidth manager comprising:

means for converting signalling data,

means for analyzing the data to be transmitted and for compressing and de-compressing data at a level of compression that is dependent on the type of data being transmitted, and

means for multiplexing a plurality of channels.

35. A bandwidth manager as in claim 34, further comprising means for identifying overflow conditions, and for establishing an overflow link to an alternative network.

36. A bandwidth manager as in claim 34 further comprising means arranged to instruct an operational computer to provide additional bandwidth in response to customer demand.

37. A switched telecommunications network comprising:

a main network including a plurality of interconnected switching devices,

a first communications link connecting a user'"'"'s site to the main network via a first of the switching devices,

a bandwidth manager provided at the user'"'"'s end of the first communications link which analyzes data to be transmitted and provides a data compression that is dependent on the type of data being transmitted,

a second communications link connecting a second user'"'"'s site to the main network via a second of the switching devices, and

a bandwidth manager provided at the user'"'"'s end of the second communications link,

the bandwidth manager of the first communications link being arranged to compress data from the associated user for transmission over the main network,

the bandwidth manager of the second communications link being arranged to decompress received compressed data for transmission to the associated user and to reconstitute the originally transmitted data, and

wherein the transmitted data remains in compressed form while being switched and transmitted by the main network.

38. A network as in claim 37, wherein the first and second communications links are fixed links.

39. A network as in claim 37, wherein the first and second communications links are radio links.