CA2126476C

CA2126476C - Multimedia call configuration system

Info

Publication number: CA2126476C
Application number: CA002126476A
Authority: CA
Inventors: Alessandro Ludovico Isidoro; Howard S. Tsai
Original assignee: American Telephone and Telegraph Co Inc
Current assignee: AT&T Corp
Priority date: 1993-08-27
Filing date: 1994-06-22
Publication date: 1998-08-25
Anticipated expiration: 2014-06-22
Also published as: JPH07154492A; CA2126476A1; EP0641133A2; US5384771A

Abstract

An improved system for effecting broadband/multimedia calls and connections within an intelligent switched telecommunication network. This system, which employs object-oriented commands, is capable of establishing complex call and connection configurations between multiple network subscribers participating in a broadband/multimedia call. These object-oriented commands, which are stored in and initiated from network adjuncts or service control points, eliminate the need for long series of individual low-level commands to be transmitted to the network switching system.
Furthermore, the system provides for a finite set of object-oriented commands which are capable of implementing the many complex and diverse interconnections which may be required in effecting multi-party broadband/multimedia calls. This is accomplished by selectively combining various object-oriented commands to produce the connectivity which will support the desired broadband/multimedia call.

Description

~26~7~

MULTIMEDIA CALL CONFIGURATION SYSTEM

BackYround Of The Invention Modern switched intelligent telecommunication networks typically comprise one or more central office switching systems trunked together, and connected 5 to lines that which are directed to the various network subscribers. A variety of communication services are provided to the network subscribers via one or more service network elements connected to the switching systems. These services range from standard voice-band audio connections (also referred to as "narrowband" connections) established between two or more network subscribers, to broadband connections which 10 allow subscribers to simultaneously exchange of audio, video, and/or digital data (such connections may be classified as "broadband/multimedia").
Within a switched telecommunication network, the network elements send predetermined commands to the switching systems relating to the particular service or services requested by a network subscriber. The switching systems configure themselves 15 in response to the commands to effect the requested services. Despite wide acceptance of intelligent network architectures in principle, there has been no clear industry consensus on how to implement and deploy such systems. The most significant issues involved are the creation and control of complex call and connection configurations in the switching systems by the services network elements, along with resolution of20 interaction between commanded services and existing switching system features.
Existing methods of handling the complex control of intelligent switching systems (such as the method put forth in the Bellcore's "Advanced Intelligent Networks Technical Advisory," TA-NWT-001112, Issue 1, May 1991) require network elements,such as adjuncts and service control points ("SCPs"), to produce a set of low level service 25 instructions to the switching system which directly manipulate call topology component resources in order to reach a desired switch configuration. These instructions directly manipulate low-level switching system resources and, therefore, contend for the use of these resources with existing switching system features. Typically, these low-level instruction sets do not follow any setpattern, and therefore result in difficultto solve feature interaction problems that directly impact all existing switch features. The required low-level transformations also are difficult to design and do not always naturally lead to a target switch configuration. The drawbacks of this type of low-level, direct manipulation of an intelligent switching system are solved with respect to narrowband 5 connections by the method and apparatus disclosed in C~n~ n Patent Application No.

2,092,591, filed on March 26, 1993. Call processing within an intelligent switching system, per the 2,092,591 application, is effectively realized from a relatively small number of target call topologies, with the switching system producing transformations from one call topology to another. Such call topologies are implemented in the switching 10 system as a set of call processing objects referred to as call configurations. The call configurations are entered into by the switching system in accordance with the commands of an object-oriented network services element that causes transformations from one call configuration to another by means of a relatively simple set of transfer commands (at least some of which represent a plurality of the low-level commands similar to those 15 proposed in the Bellcore Advisory).
Unfortunately, neither of these prior methodologies addresses the difficulties of establishing broadband/multimedia connections within a switched intelligent network. To effect a broadband/multimedia connection, two separate configurations (a call configuration, and a connection configuration) are required. This is due to the fact 20 that not all of the network subscribers participating in the call will require (or be capable of accommodating) the same type of connection to the network. For example, of the participants in an audio/video conference call, some might only require a bidirectional audio connection, others might need a bidirectional audio connection and an omnidirectional video connection, still others might require that bidirectional audio and 25 video connections be established~ Clearly, attempting to effect such a complex interconnection via the low-level instruction set of the Bellcore Advisory would require a large number of commands to be sent by network adjuncts and SCPs. Although thetarget call topologies disclosed in the 2,092,591 application offer an improvement over the low-level Bellcore instruction set, they are adapted for the establishment of 30 narrowband connections. Consequently, these target call topologies are incapable of effecting and accommodating the various call and connection configurations required within a broadband/multimedia telecommunication network.

- 2a Summary Of The Invention In accordance with one aspect of the invention there is provided a method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of: generating S a high-level call control message in response to a call topology request; executing one or more call configuration processes in response to said call topology request, thereby determining if said desired participants can accommodate the requested broadband/
multimedia call; generating a high-level connection control message, if as a result of the execution of said call configuration processes it is determined that said desired 10 participants can accommodate the requested broadband/multimedia call; and executing one or more connection configuration processes in response to said call topology request and said high-level call control message and high-level connection control message, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/multimedia call.
In accordance with another aspect of the invention there is provided a method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of:
generating a high-level control message containing a call control message and a connection control message in response to a call topology request; executing one or more 20 call configuration processes in response to said call topology request, thereby determining if said desired participants can accommodate the requested broadband/multimedia call;
executing one or more connection configuration processes in response to said call topology request and said high-level control message if as a result of the execution of said call configuration processes it is determined that said desired participants can 25 accommodate the requested broadband/multimedia call, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/multimedia call.
~ ore particularly the principles of the invention provide an improved system for effecting broadband/multimediacalls and connections within an intelligent ~ ~1 2 ~ ~ 7 6 - 2b -switched telecommunication network is provided. This system, which employs object-oriented commands, is capable of establishing complex call and connectionconfigurations between multiple network subscribers participating in a broadband/multimedia call. These object-orîented commands, which are stored in S and initiated from network adjuncts or SCPs, elimin~te the need for long series of individual low-level commandsto be transmittedto the network switching system.
Furthermore, the invention provides for a finite set of object-oriented commandswhich are capable of implementing the many complex and diverse interconnections that may be required in effecting multi-party broadband/
10 multimedia calls. This is accomplished by selectively combining various obJect-2I26~76 oriented comm~n-l~ to produce the connectivity which will support the desired broadband/multimedia call.

Brief Des~.;ption Of The Dra~inp In the drawing:
S FIG. 1 shows, in simplified block diagram form, an intelligent switched telecommunication ne~w(ilk which f~çilit~ttes the practice of the invention; andFIG. 2 shows, in simplified block diagram form, the internal architecture of service switching point 102 of FIG. 1.

Detailed DescriPtion Of The Invention FIG. 1 shows an example of an intelligent switched broadband/mllltimçdi~
public telecommnniration network which facilitates the practice of the invention. The nelwolh includes SCP 101, service switching points ("SSPs") 102, 103 and 104, and subscriber premises equipment ("SPE") 105, 106 and 107. As is known in the art, a call within an intelligent switched public telecommunication network is effected in response to control signals. In FIG. 1, these control signals are passed between SCP 101, SSP 102, SSP 103 and SSP 104 via signalling paths 108, 109, 110 and 111 (shown as dotted lines).
In lespo~lse to these signals, the SSPs reconfigure the telecommunication network to create a specific call topology and achieve the desired subscriber-to-subscriber connçction~ via transport paths 112, 113, 114, 115 and 116 (shown as bold solid lines). These transport paths may be adapted to facilitate voice, data, and/or video communiration between the network subscribers.
In effecting a given call topology within an intelligçnt switched broadbantVmultimedia public t~lecommnni~tiQn netwol~, two s~ t; configurations are established -- a call configuration ("CL-C"), and a conn~ction configuration ("CN-C"). A
CL-C defines the association belween the parties to be involved in a call, and verifies that all of the desired parties to a call are able to participate in the call. CN-Cs establish the particular type of connt-c~ions (i.e., audio, video, data ...) between the parties to a call. An individual CN-C defines a particular connection configuration, or a particular transition between existing conl-tscl ;on configurations. Some examples of the conn~tion~/tr~n~ition~
30 which a CN-C might ,~p~nt are video connections, multi-party conferencing calling, digital data transfer between parties, etc. There may be more than one CN-C associated with a given call; each establishing or modifying a particular type of connection between two or more parties. In this manner, very complex calls, involving multiple parties and a variety of media (voice, video, data ...), can be "built" from a number of simple CN-C
35 components.

2I 26~ 76 The process of effecting a call in which SPE 105 is linked via a bidirection~l audio and video conn~tion to SPE 106, and SPE 105,SPE 106 and SPE 107 are linked via a bidirectional audio connection will illustrate a particular application of the invention within the intelligent switched broadb~n-l/mllltime~ public telecommunication S nelwolk of FIG. 1. The nelwolk subscriber utili7ing SPE 105 initiates the call by sending a call topology request to setup a call to SSP 102. SSP 102 then sends the topology request to SCP 101 via ~ign~lling paths 108 and 109 (~lltom~til- tr~n~mi~sion of such requests from an SSP to an SCP is typical within intelligent public telecommunication nelwo~). Upon receipt of the topology request, SCP 101 gene,~les a high-level call 10 control mess~ge which contains information as to the identity of the parties to be included in the call, and a request for a particular CL-C which defines the association between the parties to be involved in a call (for this example, the CL-C designated CL-C2 is being requested) . This high-level call control message is then tr~n~mitt~ to requesting SSP 102 via si n~lling paths 108 and 109.
FIG. 2 shows, in simplified block diagram form, the internal architecture of SSP 102 of FIG. 1. As shown, SSP 102 in~ludes calVconnection processor 201, CL-Cmemory 202, CN-C memory 203, and switch fabric 204. Control messages received bySSP 102 via ~ign~lling path 109 are processed and nltim~t~.ly passed to switch fabric 204, thereby controlling the connectivity provided by switch fabric 204. Program-controlled electronic switching systems such as SSP 102 are known and commercially available. An example of one such switching system is the 4 ESS~ switch manufactured by AT&T, and described in The Bell System Technical Journal, Vol. 56, No. 7, September 1977. Both SSP 103 (FIG. 1) and SSP lW (FIG. 1) have the same basic architecture and o~t;,aling characteristics as SSP 102.
Upon receipt of the high-level call control message from SCP 101, calVconnection processor 201 within SSP 102 recalls CL-C2 (the requested CL-C) from CL-C memory 202, and executes the instructions cont~ined therein. CL-C memory 202 is a storage area co~ g a number of pre-programmed software modules design~te~l CL-Cl through CL-Cn -- each of which defines a specific CL-C. Software module CL-C2causes calVconnection processor 201 to send a mess~ to SSP 103 and a message to SSP
104 (via signalling paths 109, 110, and 111~. The message sent to SSP 103 requests conr~llllation that SPE 106 isn't already engaged in a call (i.e., "busy"), and that it is capable of accommodating the desired conn.-,cti~ ns (a bidirectional audio and video link to SPE 102 and a bidirectional audio link to SPE 104). The message sent to SSP 104 requests co~ tion that SPE 107 isn't busy, and that it too is capable of accommodating the desired connections (a bidirectional audio link to SPE 102 and SPE 103).
If the either SPE 103 or SPE 104 can't participate in the requested call, a negative confirmation message is returned to SPE 102 via the sign~lling paths, and the call request fails. However, assuming that both SPE 103 and SPE 104 are not busy, and can accommodate the desired colm~;~ions, two ~fflrm~tive confirm~tion mçss~s are returned to SPE 102. In response to these ~fflrm~tive co~ tion mess~gçs~ SSP 102 transmits a clearance signal to SCP 101. This clearance signal informs SCP 101 that the desired participants for the requested call are ready and able to accommodate the connections required for that call.
Upon receipt of the clearance signal, SCP 101 generates a high-level connection control message which cont~in~ a request for the particular set of CN-Cs needed to effect the network connectivity required to support the requested call. For this example, assume three CN-Cs (CN-C" CN-C2 and CN-C3) are required. This high-level connection control message is then tr~n~mitt~l to requesting SSP 102 via sign~lling paths 108 and 109. As a result of the high-level connection control message from SCP 101, calVconnection processor 201 within SSP 102 recalls the requested CN-Cs from CN-C
memory 203, and executes the instructions contained therein. CN-C memory 202 is a storage area co~ ini--g a number of pre-programmed software modules de~ign~ted CN-Cl through CN-Cn. Each of these modules defines a specific CN-C which may be used to instruct SSPs within the telecommunication network to provide the connectivity required to su~o,l a requested call. The CN-Cs stored within CN-C memory 202 are a small subset of standard configurations achievable within the telecommunication network of F~G.
1 (the specific CN-Cs stored within a given telecommnniratinn system will be a function of the type of connections which the system is foreseeably expected to accommodate).
Execution of a stored CN-Cs causes one or more comm~n(ls (similar to those disclosed in the Bellcore Advisory TA-NWT-001112) to be issued to one or more SSPs within thetelecommunication netwolk. Software module CN-Cl effects a bidirectional video connection between SPE 105 and SPE 106, and software module CN-C2 effects a bidirectional audio connection between SPE 105 and SPE 106. Software module CN-C3 effects a bidirectional audio connection bel~ SPE 105, SPE 106 and SPE 107.
Both CN-CI and CN-C2 involve connections b~ ~n SPE 105 and SPE 106.
Consequently, the execution of these CN-Cs by calVconnection processor 201 will cause instructions to be sent to switch fabric 204 of SSP 102 (the SSP that interfaces with SPE
105). In l~;.~nse to these instructions, switch fabric 204 will effect the proper connections to SPE 105 to support the requested audio and video link. In addition, the e~cec~ltion of these CN-Cs by calUconnection processor 201 will cause instructions to be tr~n~mitte~l via ~ign~lling paths 109 and 110, from SSP 102 to SSP 103 (the SSP that interfaces with SPE
106). The ~nsmitted instructions will be pl~cessed by a call/connectiQn processor within SSP 103, and result in the switch fabric of SSP 103 effecting connections to SPE 106 that support the requested audio and video link.
CN-C3 effects a bidirectional audio connection between SPE 105, SPE 106 and SPE 107. This type of CN-C, referred to as a transition, is a request to change an existing connection configuration. In this case, CN-C3 requests a transition from the 212647~

existing audio connection setup between SPE 105 and SPE 106, to a "three-way" or"conference" audio connection which includes SPE 107. Consequently, the execution of CN-C3 by calVconncc~,on processor 201 causes instructions to be tr~n~mitte~, via si~n~lling paths 109, 110 and 111, from SSP 102 to SSPs 103 and 104 (these SSPs interface with S SPE 106 and SPE 107, respectively). The transmitted instructions will be processed by a calVconnc~;~ion processors within SSP 103 and SSP 104. In response, the switch fabrics of SSP 103 and SSP 104 will effect an audio connection which links SPE 107 to the pre-existing audio com~cclion between SPE 105 and SPE 106. At this point, a confirmation signal is tr~nsmittecl from requesting SSP 102 to SCP 101, signifying completion of the 10 requested call.
By employing a flexible system of CL-Cs and CN-Cs stored within network SSPs, the above technique enables broadband/multimedia to be established within a switched intelligent public telecommunication network, without the need for the tr~n~mi~ion of long series of individual low-level c-~mm~n~l~ to or from network SSPs.
The above described technique provides for establishing broadband/multimedia call connections in an efficient and simple manner. It will be understood that the particular methods and systems described are only illustrative of the principles of the present invention, and that various modifications could be made by those skilled in the art without departing from the scope and spirit of the present invention, 20 which is limited only by the claims that follow. One such modification might include employing an adjunct linked to a network SSP to perform the processing and/or storage functions of the program-controlled SSPs described above. Another modification might include employing the invention within a private telecommunication network. Yet another modification might include the practicing of the invention in a telecommunication system 25 wherein comm~n-ls being sent between SCPs and SSPs are first routed through an intermediate service transfer point or processor. The invention might also be practiced within telecomm-mic~tinn networks wherein the functions pelÇc~ ed by the SCP in the above described example (i.e., the reception/processing of control signals, and the ~,~,ne~ ion/transmission of high-level call/connection control messages) are pelrolmed 30 within one or more program-controlled SSPs. This would naturally elimin~te the need for tr~n~mitting various control messages between the SSPs and an SCP. In all of the above embodiments, the high-level call control message and the high-level connection control mesaage could be tr~n~mitt~d as a single comm~n-l message. In such a system, the SSPs would store the single comm~n(l message and respond to the call and connection 35 co.l.pollents in a manner similar to that described above.

Claims

Claims:

1. A method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of:
generating a high-level call control message in response to a call topology request;
executing one or more call configuration processes in response to said call topology request, thereby determining if said desired participants can accommodate the requested broadband/multimedia call;
generating a high-level connection control message, if as a result of the execution of said call configuration processes it is determined that said desired participants can accommodate the requested broadband/multimedia call; and executing one or more connection configuration processes in response to said call topology request and said high-level call control message and high-level connection control message, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/
multimedia call.

2. The method of claim 1 wherein each execution of a connection configuration process effects the transition from one state of network connectivity to another state of network connectivity.

3. The method of claim 1 wherein each of said connection configuration processes is one of a fixed collection of configuration processes achievable within said intelligent switched telecommunication network.

4. A method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of:
receiving a call topology request from one of said desired participants;

generating a high-level call control message in response to a said received call topology request;
executing one or more pre-programmed call configuration processes in response to said call topology request, thereby determining if said desired participants can accommodate the requested broadband/multimedia call;
generating a high-level connection control message, if as a result of the execution of said call configuration processes it is determined that said desired participants can accommodate the requested broadband/multimedia call; and executing one or more pre-programmed connection configuration processes in response to said call topology request and said high-level control message and said high-level connection control message, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/multimedia call.

5. The method of claim 4 wherein each execution of a connection configuration process effects the transition from one state of network connectivity to another state of network connectivity.

6. The method of claim 4 wherein each of said connection configuration processes is one of a fixed collection of configuration processes achievable within said intelligent switched telecommunication network.

7. A method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of:
generating a high-level control message containing a call control message and a connection control message in response to a call topology request;
executing one or more call configuration processes in response to said call topology request, thereby determining if said desired participants can accommodate the requested broadband/multimedia call;

executing one or more connection configuration processes in response to said call topology request and said high-level control message if as a result of the execution of said call configuration processes it is determined that said desired participants can accommodate the requested broadband/multimedia call, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/multimedia call.

8. The method of claim 7 wherein each execution of a connection configuration process effects the transition from one state of network connectivity to another state of network connectivity.

9. The method of claim 7 wherein each of said connection configuration processes is one of a fixed collection of configuration processes achievable within said intelligent switched telecommunication network.

10. A method for effecting a broadband/multimedia call among a group of desired participants within an intelligent switched telecommunication network, comprising the steps of:
receiving a call topology request from one of said desired participants;
generating a high-level control message containing a call control message and a connection control message in response to said received call topology request;
executing one or more call configuration processes in response to said call topology request a said high-level control message, thereby determining if said desired participants can accommodate the requested broadband/multimedia call;
executing one or more connection configuration processes in response to said call topology request a said high-level control message if as a result of the execution of said call configuration processes it is determined that said desired participants can accommodate the requested broadband/multimedia call, thereby effecting interconnections within said intelligent switched telecommunication network which will support the requested broadband/multimedia call.

11. The method of claim 10 wherein each execution of a connection configuration process effects the transition from one state of network connectivity to another state of network connectivity.

12. The method of claim 10 wherein each of said connection configuration processes is one of a fixed collection of configuration processes achievable within said intelligent switched telecommunication network.