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innovaphone gateway
GMT
GMT (
G
reenwich
M
ean
T
ime) is the mean solar time at the Greenwich
Meridian. GMT was the world time from 1884 to 1928. It has since been
replaced in this function by the coordinated world time UTC (
U
niversal
T
ime
C
oordinated).
H
Handover
The process that take place when a DECT handset switches from one DECT
radio to another during a call.
Handset
A DECT handset is a cordless telephone.
HLC
HLC (
H
igh
L
ayer
C
ompatibility) is an information element in an ISDN, with
which the protocols and parameters that are used in layers 4 to 7 of the
speech/data channels are displayed.
H.225
H.225 is a signalling protocol standardised by the ITU-T (
I
nternational
T
elecommunication
U
nion-
T
elecommunications), which is used in H.323
networks and which supports the transfer of data, voice and video. The
protocol is used for the connection setup and shutdown, as well as for
connection control. Within the protocol, signalling is based on Q.931.
H.225 uses the RTP protocol for the real-time transfer of the multimedia
data.
H.323
H.323 is an international ITU standard (
I
nternational
T
elecommunication
U
nion) for voice, data and video communication using packet-oriented
networks, which defines the specific capabilities of terminals in the IP
environment. H.323, which is functionally comparable to the SIP protocol,
was developed for the transmission of multimedia applications and forms
the basis for VoIP. Real-time communication in LANs is defined using this
standard.
The H.323 standard consists of a whole series of protocols for signalling, the