Dialogic 05-2239-009 User Manual

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Dialogic
®
 Global Call IP Technology Guide — November 2007
121
Dialogic Corporation
IP-Specific Operations
When all of these conditions are true, the extra data associated with the GCEV_OFFERED event 
will be a GC_PARM_BLK that contains one or more parameter elements of the following type: 
IPSET_CALLINFO
IPPARM_OFFERED_FASTSTART_CODER
value = IP_CAPABILITY data structure
Each such parameter element reflects a coder specification that was contained in the call offer. If 
the offer contains multiple coder specifications, the order of the parameter elements in the 
parameter block reflects the order of the specifications in the offer message. This order reflects the 
remote endpoint’s coder preference, with the first specification being the most preferred and the 
last specification being the least preferred. If any coder properties were left unspecified by the 
remote end, the matching fields in the corresponding IP_CAPABILITY structure are filled in with 
the value GCCAP_dontCare.
If any of the four conditions described above is not true, there will be no IPSET_CALLINFO / 
IPPARM_OFFERED_FASTSTART_CODER parameter element in the parameter block associated 
with the GCEV_OFFERED.
When the IP_CAPABILITY data structure is used to convey fast start coder information, the 
direction field of the structure uses the following special value defines:
IP_CAP_DIR_RMTRECEIVE
Remote coder was specified to be Receive-only. 
IP_CAP_DIR_RMTRTPINACTIVE
Remote coder was specified with “a=inactive”, which is used in SIP to inactivate RTP 
streaming. Only supported when using SIP. 
IP_CAP_DIR_RMTRTPRTCPINACTIVE
Remote coder was specified with RTP address 0.0.0.0, which is used in SIP to inactivate both 
RTP and RTCP. Only supported when using SIP.
IP_CAP_DIR_RMTTRANSMIT
Remote coder was specified to be Transmit-only. 
IP_CAP_DIR_RMTTXRX
Remote coder was specified to be capable of both Transmit and Receive. 
4.3
Setting Call-Related Information 
The Dialogic
®
 Global Call API allows applications to set many items of call-related information. 
The following topics are presented in this section: