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ISDN Software Features

Overview

ISDN cards support the following features:

• D Channel Backup

• Information Element Library

• B Channel Negotiation

• ANI on Demand

• Vari-A-Bill Billing

D Channel Backup

ISDN cards support the D channel backup procedure as defined by Lucent TR 41459. This procedure provides a standby D channel when using NFAS. When an active D channel fails, or if there is a span alarm, the CSP converts to the standby D channel and maintains active calls. This is a provisioned option and is applicable only when using NFAS. D channel backup is supported on the T1 cards only.

ISDN Information Elements

Dialogic provides a format to send and receive Information Elements (IEs) per D channel. The data is represented using the Information Control Block (ICB) format with the ICB subtype of "Formatted IEs" (see Information Control Blocks chapter in the API Reference). This allows greater flexibility when sending a message that has different types of data to transport. Multiple Formatted IEs can be loaded in the data section of the ICB.

B Channel Negotiation

ISDN cards support B channel negotiation on incoming calls as defined in Lucent TR41459 for both E1 and T1 cards. This feature allows the user receiving the incoming call (SETUP) to negotiate for the selection of the B channel. Only B channels controlled by the same D channel are considered for the selection procedure.

ANI On Demand

ISDN cards support the Automatic Number Identification (ANI) on Demand feature as specified in Lucent TR41459. This feature allows the host to request the call originating number (calling party number) from networks that support ANI such as AT&T MultiQuest. A PPL Event Request of ANI on Demand (0x21) must be sent from the host immediately after receiving the Request For Service message from the CSP.

Vari-A-Bill Billing

ISDN cards support the Vari-A-Bill feature as specified in Lucent TR41459. This feature allows the host to request a change in billing for an incoming call. You can use this feature after a call has been answered and only if the SETUP message indicates that the network supports the flexible billing service.

See Integrated Services Digital Network.
Data channel. One of two fundamental components of an ISDN interface, it provides a path (16Kbps for BRI, 64Kbps for PRI) for carrying control signals and call data in a packet-switched mode.
Bearer channel, 64Kbps (ISDN) The channel that carries the actual payload (as opposed to D-channels, which carry signaling data that helps route the payload).
See Automatic Number Identification.
See Non Facility Associated Signaling.
Digital communications link - voice, data, and video at a 1.544 Mbps rate (24 64 Kbps channels)
Name for the data fields within an ISDN Layer 3 message. See Integrated Services Digital Network.
See Information Control Block.
ICB. A standardized block that allows control data to be inserted in a standard way into API messages.
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.
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 Programmable Protocol Language.
RFS. A Status Message indicating that some entity is requesting service from the Excel platform.