Dialogic 6.2 manual L43.data.enable, November 319

ISDN Call Processing Overview

Notification of incoming calls comes via a SETUP_IND message which contains the B-channel number the network would like to set the call up on. By turning on negotiation, you can specify a different (specific) B-channel on which to establish rather than the one requested by the network. In this case, a CALL PROCEEDING message will not get sent to the network and it is your responsibility to notify the network of the desired B-channel via any one of the following three messages: L4L3mCALL_PROCEEDING_REQUEST, L4L3mALERTING_REQUEST, and L4L3mCONNECT_REQUEST.

Note: If using more than one of these messages, you should be consistent on the B-channel value.

You might want to do B-channel negotiation in situations where each of the channels is hard-code mapped to different locations depending on the type of call (data, voice, fax) received. If an incoming call to a channel is not the type of call that is handled by that (network-assigned) channel, then it must be (re)established on a channel that can handle the type of that call, or else the call won’t be handled properly.

This feature is turned on by setting:

l43.data.enable_protocol.level3.cnfg.q931.b_chan_negot=1

in the ENABLE_PROTOCOL message. In the case where the network indicates that the B-channel it is offering is non-negotiable,

and the l43.data.enable_

protocol.level3.cnfg.q931.proc_on_exclusv field was set when the protocol was enabled, the calling process will proceed with a CALL PROCEEDING message being sent to the network without requiring you to indicate one. The network indicates that the B-channel it is offering is non-negotiable. The user had agreed to proceed by having set the proc_on_exlusv field.

Connect Acknowledge is reported to the module but is not automatically reported to the host via the Bfv API. In order to retrieve L3L4mCONN_ACK_IND, set the field below to 1 in your ENABLE_PROTOCOL message:

l43.data.enable_protocol.level3.cnfg.q931.subscribe_connack=1

The stack can consider the call connected after sending the L4L3mCONNECT_REQUEST message or wait until it receives the CONNECT ACKNOWLEDGE from the network. If you do not want to wait for the network response, set the field below to 1 in your ENABLE_PROTOCOL message:

l43.data.enable_protocol.level3.cnfg.q931.no_rx_conn_ack=1

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