Dialogic M7324 사용자 설명서

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Dialogic
® 
PBX Integration Board User’s Guide 
may be sent outside the PBX if outside networks also use digital circuits; 
however, they are usually converted back to analog voice signals. 
PBXs use control information to instruct their station sets to perform specific 
functions such as setting the message waiting indicator and call transfer. This 
control information is sent using proprietary digital protocols. A protocol is a set 
of rules relating to the format and timing of data transmissions. These protocols 
not only contain control information, but also “message” data that can be used to 
significantly enhance computer telephony (CT) applications that use PBX call 
control elements such as called/calling number ID.  
The term “computer telephony” refers to the ability to interact with computer 
databases or applications from a telephone. Computer telephony technology 
supports applications such as: 
•  automatic call processing 
•  automatic speech recognition 
•  text-to-speech conversion for information-on-demand 
•  call switching and conferencing 
•  unified messaging  
•  voice mail and voice messaging 
•  fax systems, including fax broadcasting, fax mailboxes, fax-on-demand, and 
fax gateways 
•  transaction processing such as Audiotex and Pay-Per-Call information 
systems 
•  call centers  
PBXs can communicate with their station sets using in-band or out-of-band 
signaling. In-band signaling is a method used by analog (2500) telephones (e.g., 
calling into a PBX and using DTMF to respond to voice prompts). In-band 
signals use the same band of frequencies as the voice signal. This method 
provides limited integration because there are no standards and different PBXs 
provide varying levels of control.  
Out-of-band signaling is used by PBXs to send and receive data from station sets 
or a CT computer. This data can include information such as called/calling 
number ID. Out-of-band signals do not use the band of frequencies used by the 
voice signals. They can be transmitted using the same wires as the telephone set, 
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