Nat Traversal - Draytek VIGOR3300V+ User Manual

4.7.8 NAT Traversal

NAT traversal is a challenge that all Service Providers looking to deliver public IP-based
voice and multimedia services must solve. The goal of this function is to provide secure
connection to subscribers behind NAT (Network Address Translation) devices and Firewalls.
Overcoming this traversal problem will lead to widespread deployment of profitable voice
and multimedia over IP services to any subscriber with broadband connection.
Disable
Manually Input NAT IP
Address
Auto Discovery NAT IP
Address
Disables this function. The feature is used if Vigor3300 has a
public WAN IP address and not behind a NAT router.
NAT IP Address - Type the IP address to be used as the NAT
IP address. The feature is used when Vigor 3300V is behind a
NAT router, and the NAT router uses a static WAN IP
address. This value is the same as the WAN IP of the front
NAT router.
It is used when Vigor3300 is behind a NAT router, and the
NAT router uses a dynamic WAN IP address such as a DHCP
or PPPoE client. The Vigor3300 requires a STUN server for
this option.
The "STUN" (Simple Traversal of UDP through NATs)
server is an implementation of the STUN protocol that
enables STUN functionality in SIP-based systems. It is an
application-layer protocol that can determine the public IP
and nature of a NAT device sitting between the STUN client
and STUN server.
Semi-auto, need to config NAT – If you click this function;
the user needs to configure NAT information.
Full-auto, no need to config NAT (only for SIP)- If you
click this function; the user does not configure NAT
information.
STUN Local Port - Type the port number of the STUN
server.
STUN Server Address - Type the IP address of the STUN
server.
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Vigor3300V+ Series User's Guide