User guide

Chapter 4: Configuring your VOIP
Multi-Tech Systems, Inc. 53
NAT Traversal
Setting the NAT Traversal parameters. NAT (Network Address Translation) parameters are applicable only when
the MultiVOIP is operating in SIP mode. The use of STUN (Simple Traversal of UDP NATs) servers to aid
networks with NAT devices can be found in RFC 3489, the Request for Comments document available from the
Internet Engineering Task Force.
Figure 4-23: NAT Traversal
Descriptions for NAT Traversal screen fields are presented in the table below.
NAT Traversal Definitions
Field Name
V
alues Description
Enable (STUN) Y/N Enables STUN client functionality in the MultiVOIP.
STUN (Simple Traversal of UDP through NATs (Network Address Translation))
is a protocol that allows a server to assist client gateways behind a NAT firewall
or router with their packet routing.
Name/IP (Server)
n.n.n.n
IP address of the STUN server.
Port (Server;
NAT/STUN)
port; The data port (TDM time slot) at which STUN info will be transmitted and
received. Default= 3478
Keep Alive (Timers;
NAT/STUN)
60 – 3600
(seconds)
The interval at which the STUN client sends indicator (“Keep Alive”) packets to
the STUN server to determine whether or not the STUN server is available.