VoIP gateway IP400 version 5.01
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The device transmits its identity and IP address once the gatekeeper has been
identified. This can be a logical name, a telephone number or both. The device is
ready for operation and accessible if the ID is OK. Devices that log on to the gate-
keeper using the RAS protocol are configured in
Gatekeeper client group
mode
.
Fig. 20 Call sequence with two gatekeepers and RAS
Tip
Many gatekeepers and also some VoIP devices do not support the Discovery
procedure. In this case the gatekeeper's IP address has to be configured in
the device to be registered. Likewise, multicasts of routers are not usually
transmitted. That is why the IP address of the gatekeeper also has to be reg-
istered if it is separated from the registering device by a router.
Legend:
---- Device
mgmt. (RAS)
......Call signalling
(H.225)
___ Voice data
(RTP)
G
atek
eepe
r 2
Gatek
ee
per 1
IP telephone
ISDN
Gateway
ISDN
Eqpt.
mgmt.
Call
switch-
ing
Call
switch-
ing
Eqpt.
mgmt.