ATM-based distributed virtual tandem switching system

A method for transporting voice from an originating location to a destination across an Asynchronous Transfer Mode (ATM) network via an originating trunk interworking function (T-IWF) device and a terminating T-IWF device, the method comprising:

• transmitting the voice from the originating location to an originating trunk that leaves an end office switch;
• converting the originating trunk to ATM cells;
• interfacing between narrowband and broadband signaling for call processing and control within the ATM network, wherein a centralized control and signaling interworking function (CS-IWF) device provides call processing and control information to the originating and terminating T-IWF devices via the ATM network;
• transmitting the voice within the ATM cells across the ATM network utilizing the broadband signaling;
• converting the ATM cells to a destination trunk;
• and
• transmitting the voice from the destination trunk to the destination.

An Asynchronous Transfer Mode (ATM) based distributed virtual tandem switching system in which a network of ATM-based devices is combined to create a distributed virtual tandem switch, the system comprising:

• an ATM switching network that dynamically sets up individual switched virtual connections;
• a trunk interworking function (T-IWF) device that converts end office voice trunks from TDM channels to ATM cells by employing a circuit emulation service;
• and
• a centralized control and signaling interworking function (CS-IWF) device that performs call control functions and interfaces narrowband signaling and broadband signaling for call processing and control within the ATM switching network, the CS-IWF device providing call processing and control information to the T-IWF device via the ATM switching network;
• wherein the ATM based distributed virtual tandem switching system is adapted to comprise a virtual switch in a PSTN.

An Asynchronous Transfer Mode (ATM) distributed virtual tandem switch comprising:

• a centralized control and signaling inter-working function (CS-IWF) device that performs call control functions and converts between narrowband and broadband signaling for call processing and control within an ATM switching network;
• a first trunk inter-working function (T-IWF) device that converts trunks from end office switches to ATM cells, the first T-IWF device receiving call processing and control information from the CS-IWF device via the ATM switching network;
• and
• a second trunk inter-working function (T-IWF) device that converts ATM cells to trunks for end office switches, the second T-IWF device receiving call processing and control information from the CS-IWF device via the ATM switching network;
• wherein telephone calls originating and terminating within an advanced intelligent network are transmitted through the ATM switching network.

An Asynchronous Transfer Mode (ATM) distributed virtual tandem switching system comprising:

• an ATM switching network;
• a first trunk inter-working function (T-IWF) device that converts trunks from end office switches to ATM cells;
• a second trunk inter-working function (T-IWF) device that converts ATM cells to trunks for end office switches;
• and
• a centralized control and signaling interworking function (CS-IWF) device that performs call control functions and converts between narrowband and broadband signaling for call processing and control within the ATM switching network, the CS-IWF device providing call processing and control information to the first and second T-IWF devices via the ATM switching network, wherein the ATM distributed virtual tandem system functions like a standard tandem switch.

An Asynchronous Transfer Mode (ATM) distributed virtual tandem switching system comprising:

• an originating end office that originates a telephone call and forwards appropriate narrowband signaling for call processing and control within an advanced intelligent network;
• a signaling transfer point that receives and forwards narrowband signaling for call processing and control within the advanced intelligent network;
• and
• a centralized control and signaling interworking function (CS-IWF) device that performs call control functions and converts between narrowband and broadband signaling for call processing and control within an ATM switching network, the CS-IWF device providing call processing and control information to trunk interworking function (T-IWF) devices via the ATM switching network;
• wherein the CS-IWF device receives narrowband signaling from the signaling transfer point and processes and controls the telephone call within the ATM switching network using broadband signaling based upon the received narrowband signaling.

An Asynchronous Transfer Mode (ATM) distributed virtual tandem switching system comprising:

• an ATM switching network;
• an originating end office that originates a telephone call;
• a terminating end office that is the destination of the telephone call;
• a first trunk inter-working function (T-IWF) device that converts trunks from end office switches to ATM cells;
• a second trunk inter-working function (T-IWF) device that converts ATM cells to trunks for end office switches;
• a signaling transfer point that receives and forwards narrowband signaling for call processing and control within an advanced intelligent network;
• and
• a centralized control and signaling interworking function (CS-IWF) device that performs call control functions and converts between narrowband and broadband signaling for call processing and control within the ATM switching network, the CS-IWF device providing call processing and control information to the first and second T-IWF devices via the ATM switching network;
• wherein the ATM distributed virtual tandem system functions like a standard tandem switch.

A method for transporting voice across an Asynchronous Transfer Mode (ATM) network, the method comprising:

• transmitting the voice from an originating location to an ATM network;
• transmitting narrowband signaling;
• converting between narrowband signaling and broadband signaling for call processing and control within the ATM network;
• and
• transmitting the broadband signaling through the ATM network for call processing and control.