Dialogic 05-2239-009 User Manual

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Dialogic Corporation

Possible values (corresponding to events that can be added or removed from the mask are) are:

EXTENSIONEVT_DTMF_ALPHANUMERIC 

For notification of DTMF digits received in User Input Indication (UII) messages with 
alphanumeric data. When using SIP, this value is not applicable. 

EXTENSIONEVT_SIGNALING_STATUS 

For notification of intermediate protocol state changes in signaling (in H.323, for example, 
Q.931 Connected and Disconnected) and control (in H.323, for example, H.245 Connected 
and Disconnected).

EXTENSIONEVT_STREAMING_STATUS 

For notification of the status and configuration information of transmit or receive directions of 
media streaming including: Tx Connected, Tx Disconnected, Rx Connected, and Rx 
Disconnected.

The application can receive notification of changes in the status (connection and disconnection) of 
media streaming in the transmit and receive directions as GC_EXTENSIONEVT events. When the 
event is a notification of the connection of the media stream in either direction, information about 
the coders negotiated for that direction and the local and remote RTP addresses is also available. 

The events for this notification must be enabled by setting or adding the bitmask value 
EXTENSIONEVT_SIGNALING_STATUS to the GC_EXTENSIONEVT mask; see 

, on page 154. Once the events are 

enabled, when a media streaming connection state changes, the application receives a 
GCEV_EXTENSION event. The EXTENSIONEVTBLK structure pointed to by the extevtdatap 
pointer within the GCEV_EXTENSION event will contain the following information for all media 
streaming status changes: 

extID 

IPEXTID_MEDIAINFO 

parmblk  

A GC_PARM_BLK containing the protocol connection status with the 
IPSET_MEDIA_STATE parameter set ID and one of the following parameter IDs: 

IPPARM_TX_CONNECTED – Media streaming has been initiated in transmit direction. 
The parameter value is an IP_CAPABILITY structure containing the coder configuration 
that resulted from the capability exchange with the remote peer. 

IPPARM_TX_DISCONNECTED – Media streaming has been terminated in transmit 
direction. No parameter value is used with this parameter ID. 

IPPARM_RX_CONNECTED – Media streaming has been initiated in receive direction. 
The parameter value is an IP_CAPABILITY structure containing the coder configuration 
that resulted from the capability exchange with the remote peer. 

IPPARM_RX_DISCONNECTED – Media streaming has been terminated in receive 
direction. No parameter value is used with this parameter ID. 

IPPARM_TX_SENDONLY – Media streaming has been initiated for a half-duplex 
transmit-only connection. The parameter value is an IP_CAPABILITY structure 
containing the coder configuration that resulted from the capability exchange with the 
remote peer.