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Call Control - Tones Generation and Reception

Address Signaling Tones

Configure the CSP to generate outbound DTMF, MFR1, or MFR2 address signaling. To initiate outpulsing, use the "Outpulse Stage N Address Digits" ICB in the Route Control or Outseize Control message. The host can supply outpulsed digits and inform the CSP of the signaling tone type and where to retrieve the digits.

Call Progress Tone Patterns

The Connect Tone Pattern message generates call progress tone patterns. A pattern is generated for an active call only, incoming or outgoing. The Connect Tone Pattern message then connects the channel to the pattern specified by the Pattern ID.

Tone Reception

The CSP provides tone reception for collecting digits and for analyzing call progress. The CSP software maintains separate tone receiver pools for DTMF, MFR1, MFR2 (Backward and Forward) and call progress reception, dynamically configured and verified upon start-up. These pools are shared by all channels.

Address Signaling Tones

This section describes the different types of Address Signaling tones.

Digit Collection During Call Setup:

During call setup, the CSP can collect DTMF, MFR1, and MFR2 (Forward and Backward) digits.

Important! Any card with an MFR2 receiver must also have an MFR2 forward and backward transmitter configured. If a card has only receivers, an incoming call triggers a DSP Function Not Configured alarm.

You can program the CSP to automatically collect inpulsing address data, which identifies the Dialed Number Identification Service (DNIS) and/or the Automatic Number Identification (ANI). Applications can use the address data to authenticate subscribers and to identify services.

During call setup, the host uses a combination of the DSP SIMM Configure, Inpulsing Parameter Configure, and Inseize Control messages to program digit collection at the Signaling Layer 3. The message features are described below. Please refer to the API Reference for details:

• DSP SIMM Configure – Configures the function of a DSP. Tone reception functions include DTMF, MFR1, MFR2, and E1 Dial Pulse reception. (E1 Dial Pulse not available on the DSP Series 2 card).

• Inpulsing Parameters Configure – Configures parameters for collecting inpulse data at the Signaling Layer 3. Inpulsing parameters define the address signaling type, the number of digit strings, and the collection method used during call setup.

The CSP supports four different inpulsing stages, each with one or two digit strings. When the host instructs the CSP to collect address signaling information (typically in-band dual frequency tones) it also specifies a preprogrammed inpulsing stage that describes how to perform the digit collection. Options for configuring the inpulsing stage include the following:

• Address signaling type (DTMF, MFR1, MFR2)

• Number of strings (1 or 2)

• String collection method (fixed number of digits, KP/ST framed, compelled)

• Inseize Control – Sends inseize instructions to the CSP to control incoming call setup during real-time call processing at the Signaling Layer 3. The Receive Stage N Address Data instruction allocates and attaches a DSP to a channel to collect the incoming digit stream.

A maximum of 100 digits can be collected within a single inpulsing stage. Use the Inseize Instruction List Configure message to preprogram instructions on a channel at the Signaling Layer.

The Report Incoming Call With Address Digits instruction sends a Request for Service With Data message to the host, with the single-stage or multiple-stage digit streams collected.

Digit Collection After Call Setup

After a call is set up, the CSP performs interactive DTMF digit collection. The host collects additional information, either one digit at a time with the DSP Service Request message, or as a string of digits with the Collect Digit String message. These messages are processed by the CH component.

• DSP Service Request - allocates and attaches a digit receiver to a channel. The digit receiver remains attached and uses the Call Processing Event message to report digits as they are decoded. The receiver remains attached to the channel until the channel is released or until the host uses the DSP Service Cancel message to cancel digit collection.

• Collect Digit String - allocates and attaches a digit receiver to a channel, but unlike the DSP Service Request message, it directs the CSP to collect a string of digits until a termination condition is reached. The termination condition could be either:

• the detection of a particular digit from a termination digit set

• a fixed number of digits collected

• a timeout
When a termination condition occurs, the CSP reports all of the digits collected in the Call Processing Event message and the receiver is returned to the system receiver pool. When the CSP detects the first valid digit, it automatically cancels any prompting tone or recorded announcement being played out to that channel.

See Information Control Block.
Outgoing call setup during real-time call processing on a specific channel.
A tone sent to the caller indicating the progress of the call. Examples include dial tone, busy tone, ringback tone, and comfort noise (digital cellular).
Digital Signal Processor
Directory Number Information Service
ANI. This feature allows a host to request the call originating number (calling party number) from networks that support Automatic Number Identification such as AT&T MultiQuest.
See Automatic Number Identification.
Protocol layer of the CSP.
A digital communications link - voice, data, and video at a 2.048 Mbps rate; 30B/2D or 31B/1D (ISDN); non-North American version of T1.
Incoming call setup during real time call processing on a specific channel.