Communications method and apparatus

• US 6,937,612 B1
• Filed: 12/31/1998
• Issued: 08/30/2005
• Est. Priority Date: 07/03/1998
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Rose, Desne Jean, Mauger, Roy Harold
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): Boakye, Alexander O.
• Application Number:
  US09/222,019
• Time in Patent Office: 2,434 Days
• Field of Search: 370/261, 370/465, 370/469, 370/395.52, 370/356, 370/391, 370/474, 370/352, 370/524, 370/354, 370/401, 370/467, 370/522, 370/410, 370/353, 370/400, 370/389, 370/397
• US Class Current: 370/465
• CPC Class Codes: H04L 65/1043 Gateway controllers, e.g. media gateway control protocol [MGCP] controllers
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/1106 Call signalling protocols; H.323 and related
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/24 Negotiation of communication capabilities
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04M 7/125 Details of gateway equipment

Abstract

A method for enabling traffic to be carried between devices which may use different communications protocols employs a multimedia service provide, which provides an interface between two devices or between a device and a multimedia network. The service provider enables conversion between the communications protocols used by the two devices by comparing the protocols used by each device and, preferably, carrying out a conversion which minimises the amount of traffic conversion required. If two devices are interfaced to an intermediate network via respective service providers, the service providers preferably negotiate before communication between the devices begins to ensure, if possible, that traffic conversion is only performed by one of the service providers. Each device is connected to the service provider at a network access server of a type matched to the device type and traffic conversion is carried out as required using an Asynchronous Transfer Mode Virtual Channel switch controlled by a multimedia server.

Claims

1. A method for carrying communications traffic between first and second devices of the same or different types, the first device being coupled to a service provider, the second device being coupled to an exchange distant from the service provider, and the service provider and exchange being coupled for communication across an intermediate network, comprising the steps of:

receiving at the service provider a call signal from the first device, the call signal containing an address of the second device;

setting up a preliminary communications link between the service provider and the exchange to exchange information as to the capabilities of the first and second devices, the information exchanged on the preliminary link including at least one of a communications standard, a desired data rate and a type of data for transmission by the first terminal and, in reply, associated reception capabilities of the second terminal as a subset of the capabilities of the first terminal;

using the information at the service provider to determine a procedure for converting, if necessary, traffic for transmission between the first and second devices; and

,

setting up a call to transmit the traffic between the first and second devices, converting the traffic as necessary.

2. A method according to claim 1, in which the exchange is a second service provider.

3. A method according to claim 1, in which the service provider determines information as to the at least one of communications protocol, desired data rate and the type of data for transmission by the first terminal by inspecting the call signal and traffic received by the service provider from the first device.

4. A method according to claim 1, in which traffic from and to the first device can be converted between different communications protocols by the service provider.

5. A method according to claim 1, in which the first device is one of a plurality of devices of the same or different types coupled to the service provider for communicating with each other via the service provider and, if present, via the network.

6. A method according to claim 1, in which the procedure for converting traffic, if necessary, is determined so that traffic conversion is only carried out once, if possible, during transmission of traffic from the first device to the second device.

7. A method according to claim 1, in which the procedure for converting the traffic, if necessary, for transmission between the first and second devices is selected so as to minimise the conversion required.

8. A method according to claim 1, in which traffic can be transmitted across the network using any of a plurality of protocols, and in which the procedure for converting the traffic, if necessary, for transmission between the first and second devices is selected so as to minimise the conversion required.

9. A method according to claim 8, in which one of the plurality of protocols is a preferred protocol for traffic transmission across the network and in which the procedure for converting traffic, if necessary, is determined so as to maximise the, use of the preferred protocol or protocols compatible therewith on the network so that, if traffic transmission from the first device to the second device involves conversion into the preferred protocol or a compatible protocol, then the conversion is performed by the service provider before transmission on the network and, if transmission from the first device to the second device involves conversion from the preferred protocol or a compatible protocol into a less-preferred protocol, then the conversion is performed after transmission across the network and before reception by the second device.

10. A method according to claim 1, using a set of control messages to control media paths across the intermediate network between the first and second devices, comprising the step of;

establishing a control channel across the intermediate network to carry the set of control messages;

intercepting the control messages in the service provider and determining a requirement for media paths in response thereto; and

in response to the determination setting up a media path or paths in the intermediate network for carrying traffic between the first and second devices.

11. A method according to claim 1, comprising carrying a plurality of traffic components across the network from the first device, the method comprising the steps of:

in the first device, generating control messages for controlling the traffic components and applying these control messages to the service provider;

establishing a communication path within the network to carry at least one of the plurality of traffic components; and

in the network, using the control messages to control transfer of the plurality of traffic components over the communication path.

12. A method according to claim 1, in which the intermediate network has a transfer protocol that supports mini-channels in a virtual-circuit-switched environment, the first device providing the communication traffic as traffic streams to the service provider and the method comprising the step of mapping the streams to the mini-channels.

13. A method according to claim 1 in which the traffic comprises at least one of audio, video and data signals and multimedia traffic.

14. A method according to any claim 1 in which the first device comprises any of an SS7 signalling device, an H323 terminal, an H324 terminal, an H320 terminal, an H310 terminal, an H321 terminal, a telephone or a PBX, and in which the first device is coupled to the service provider via any of a LAN, a modem, and an ISDN line.

15. A method for operating a service provider as defined in claim 1.

16. A computer-readable storage medium having a program recorded thereon, where the program is to make a computer implement a method as defined in claim 1.

17. A communications apparatus forming a service provider for establishing communication between a first device coupled to the service provider and a second device coupled to an exchange distant from the service provider, the service provider and the exchange being coupled for communication across an intermediate network;

the apparatus comprising;

a network access server coupled to the first device;

a traffic supervisor responsive to a call signal received by the server from the first device for setting up a call between the first and second devices by setting up a preliminary communications link between the service provider and the exchange to exchange information as to the capabilities of the first and second devices and using the information at the service provider to determine a procedure for converting, if necessary, traffic for transmission between the first and second devices, and then establishing a media path across the network between the first and second devices;

a traffic means controlled by the traffic supervisor for transferring the traffic between the first and second devices across the media path, and converting the traffic, if necessary, according to the determined procedure;

wherein the traffic is carried by ATM across the network and the traffic means comprises an ATM virtual-channel switch.

18. A communications apparatus according to claim 17, in which the traffic supervisor comprises a call supervisor, a media handler and a connection handler, and in which;

the call supervisor responds to the call signals from the first device to identify an address for the second device;

the media handler determines the type of the first device and the type of traffic to be communicated to the second device by inspecting signals received from the first device via the server, controls the exchange of information with the second device, and determines the procedure for converting the traffic, if necessary; and

the connection handler controls the operation of the traffic means.

19. A communications apparatus according to claim 17, in which the network access server translates control information from the first device into a predetermined protocol for input to the traffic supervisor.

20. A communications apparatus according to claim 19, in which the predetermined protocol is an H323 standard.

21. A communications apparatus according to claim 17, in which the traffic supervisor controls the network access server to convert the traffic to and/or from the first device, if necessary.

22. A communications apparatus according to claim 17, in which the network access server can convert traffic to and/or from the protocol used by the first device from and/or to any of a plurality of protocols compatible with other devices with which the first device may communicate.

23. A communications apparatus according to claim 17, comprising a plurality of network access servers for coupling to a plurality of devices of the same or different types, each network access server being compatible with the type of device to which it is coupled.

24. A communications apparatus according to claim 17, comprising a network access server having a plurality of ports for coupling to a plurality of devices of the same or different types, the network access server being able to identify traffic from each device type and to convert traffic to and/or from the standard used by each device type from and/or to any of a plurality of standards compatible with other devices for communication.

25. A communications apparatus according to claim 17, in which the traffic supervisor determines the procedure for converting the traffic, if necessary, so as to increase the efficiency of communication between the first and second devices.

26. A communications apparatus according to claim 17, in which the traffic supervisor orchestrates the communication of traffic components between first and second devices via the intermediate network, the traffic supervisor being responsive to control messages communicated between the first and second devices, and the traffic supervisor including;

means for setting up a communication path for carrying the control messages across the intermediate network;

means for determining types of control message sent across the communication path; and

means for establishing media paths dependent upon types of control message sent across the communication path, the media paths arranged to transfer the traffic components across the intermediate network.

27. A service provider as defined in claim 17.

28. A communications system comprising a service provider as defined in claim 17.

29. A computer-readable storage medium having a program recorded thereon, where the program is to make a computer implement a method for carrying communications traffic between first and second devices of the same or different types, the first device being coupled to a service provider, the second device being coupled to an exchange distant from the service provider, and the service provider and exchange being coupled for communication across an intermediate network, comprising the steps of:

receiving at the service provider a call signal from the first device, the call signal containing an address of the second device;

setting up a preliminary communications link between the service provider and the exchange to exchange information as to the capabilities of the first and second devices;

the information exchanged on the preliminary link including at least one of a communications standard, a desired data rate and a type of data for transmission by the first terminal and, in reply, associated reception capabilities of the second terminal as a subset of the capabilities of the first terminal;

using the information at the service provider to determine a procedure for converting, if necessary, traffic for transmission between the first and second devices; and

, setting up a call to transmit the traffic between the first and second devices, converting the traffic as necessary.

30. A method for carrying communications traffic between first and second devices of the same or different types, the first device being coupled to a service provider, the second device being coupled to an exchange distant from the service provider, and the service provider and exchange being coupled for communication across an intermediate network, comprising the steps of;

receiving at the service provider a call signal from the first device, the call signal containing an address of the second device, the service provider determining information as to the at least one of a communications protocol, a desired data rate and a type of transmission by the first terminal by inspecting the call signal and traffic received by the service provider from the first device;

setting up a preliminary communications link between the service provider and the exchange to exchange information as to the capabilities of the first and second devices;

using the information at the service provider to determine a procedure for converting, if necessary, traffic for transmission between the first and second devices; and

,

setting up a call to transmit the traffic between the first and second devices, converting the traffic as necessary.