Dialogic Global Call IP Benutzerhandbuch

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Dialogic
®
 Global Call IP Technology Guide — November 2007
597
Dialogic Corporation
Glossary
alias: A nickname for a domain or host computer on the Internet.
blind transfer: See unsupervised transfer.
call transfer: See supervised transfer and unsupervised transfer.
codec: A device that converts analog voice signals to a digital form and vice versa. In this context, analog signals 
are converted into the payload of UDP packets for transmission over the internet. The codec also performs 
compression and decompression on a voice stream.
H.225.0: Specifies messages for call control including signaling, Registration Admission and Status (RAS), and 
the packetization and synchronization of media streams.
en-bloc mode: A mode where the setup message contains all the information required by the network to process 
the call, such as the called party address information.
H.245: H.245 is a standard that provides the call control mechanism that allows H.323-compatible terminals to 
connect to each other. H.245 provides a standard means for establishing audio and video connections. It specifies 
the signaling, flow control, and channeling for messages, requests, and commands. H.245 enables codec selection 
and capability negotiation within H.323. Bit rate, frame rate, picture format, and algorithm choices are some of the 
elements negotiated by H.245.
gateway: Translates communication procedures and formats between networks, for example the interface 
between an IP network and the circuit-switched network (PSTN).
Gatekeeper: Manages a collection of H.323 entities (terminals, gateway, multipoint control units) in an H.323 
zone.
H.255.0: The H.255.0 standard defines a layer that formats the transmitted audio, video, data, and control streams 
for output to the network, and retrieves the corresponding streams from the network. 
H.323: H.323 is an ITU recommendation for a standard for interoperability in audio, video and data transmissions 
as well as Internet phone and voice-over-IP (VoIP). H.323 addresses call control and management for both point-to-
point and multipoint conferences as well as gateway administration of IP Media traffic, bandwidth and user 
participation.
IP: Internet Protocol
IP Media Library: Dialogic API library used to control RTP streams.
Multipoint Control Unit (MCU): An endpoint that support conferences between three or more endpoints.
prefix: One or several digits dialed in front of a phone number, usually to indicate something to the phone system. 
For example, dialing a zero in front of a long distance number in the United States indicates to the phone company 
that you want operator assistance on a call.