Siemens Gigaset DE380 IP R - Manual (Page 35)

34
Configuring the phone via the Web configurator
For incoming calls
If port forwarding is activated or a DMZ is set up for the phone on the router,
no special settings are required for incoming calls.
If this is not the case, an entry in the NAT routing table (in the router) is neces-
sary in order for the phone to be reached. This entry is created when the phone
is registered with the SIP service.
For outgoing calls
The phone needs its public address in order to receive caller voice data.
There are two possibilities:
u The phone requests the public address from a STUN server on the Internet
(Simple Transversal of UDP over NAT). STUN can only be used with asymmet-
ric NATs and non-blocking firewalls.
u The phone does not direct the connection request to the SIP proxy but to an
outbound proxy ("Server Settings"
¢
page 32) on the Internet that supplies
the data packets with the public address.
The STUN server and outbound proxy are used alternately to work around the
NAT/firewall in the router.
STUN
Activate the checkbox if you want your phone to use STUN as soon as it is
used on a router with asymmetric NAT.
STUN Server Address (only if STUN is activated)
Enter the (fully-qualified) DNS name or the IP address of the STUN server on
the Internet.
STUN server port (only if STUN is activated)
Enter the number of the communication port on the STUN server.
The default port is 3478.