Dialogic Global Call IP Benutzerhandbuch

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Dialogic Corporation

The media management interface required to support in-band DTMF transport is not available 
when the Dialogic

®

 Global Call API is initialized in 3PCC mode. As a result, the application must 

use IP Medai Library functions to specify the type of DTMF transport to use (in-band or out-of-
band).

When the Dialogic

®

 Global Call API is initialized in 3PCC mode, the Dialogic

®

 Global Call API 

library does not provide support for T.38 fax or in-band tone detection. The host application is 
responsible for performing T.38 signaling through re-INVITE functionality and the SDP. 

The session description protocol (SDP) is the method of choice for communicating device 
capabilities between SIP endpoints. SDP is transported as payload in SIP message bodies. SDP is 
used to exchange endpoint capability information such as coder support, IP address, port 
information and media stream direction. The SDP information is required to manage media 
resources, such as IPM devices and RTP media streams.

The host application must parse the SDP information incoming Dialogic

®

 Global Call API events. 

Likewise, the host application must insert SDP content into the make call parameter block before 
making a call. 

The Dialogic

®

 HMP Software includes an example SDP generator/parser. The default installation 

path for the example SDP generator/parser is %INTEL_DIALOGIC_DIR%\demos, where 
%INTEL_DIALOGIC_DIR% is the environment variable for the directory in which the Dialogic

®

 

HMP Software is installed. The example includes:

demo application

source code

binary code

design diagrams

The following third party call control message sequence diagrams are included: