XnetSolutions SX-GATE, Руководство пользователя

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14.9.2 SIP proxy 436
Only IP phones connected to the SX-GATE interface eth0 can
use the SIP proxy. The proxy supports UDP only.
There are two ways to use the SIP proxy:
Outbound proxy with external registrar
In this case the IP phones register with a registrar in the Internet. Supplemental
services like a voice box or a gateway into the public telephone system. Here
the primary task of SX-GATE's proxy is to forward incoming calls to the correct
IP phone.
Calls to internal IP phones will not be routed through the
external registrar.
If the Internet IP of SX-GATE is dynamic, a short
registration interval has to be configured in the IP phone.
A re-registration is the only means to inform the registrar
of an IP change. Thus the registration interval determines
the maximum period of time a local IP phone will be
unreachable after an IP change.
To configure this scenario you have to configure the internal IP address of SX-
GATE as the outbound proxy in the SIP phones. Ask your VoIP provider about
the username, password and the name of the registrar server.
Local registrar
SX-GATE's SIP proxy can also act as a simple registrar. An appropriate DNS
entry must point to the external IP of SX-GATE to allow incoming calls.
If the external SX-GATE IP is dynamic you will have to
use dynamic DNS. After an IP change the time required
to update the DNS entry determines how long the local IP
phones will be unreachable. The registration interval of the
IP phones has no influence.
Configure the IP phones as follows: Enter the DNS name as registrar server. The
username is arbitrary but must of course be unique. The username is used to
determine the local destination of the call. Finally the internal IP of SX-GATE has
to be configured as outbound proxy.