Konftel 300IP Installation Manual page 21

SETTINGS
of IP telephony keep track of the actual IP address used to register a phone, and the one
used in the SIP requests from the same phone, and then replaces the addresses in the
SIP messages.
STUN
STUN host
Offer ICE
TURN
TURN User
TURN host
Password
On phone: MENU > SETTINGS > ADVANCED > (PIN) > NAT TRAVERSAL (6,2,3).
STUN (Simple Traversal of UDP through NATs) is a protocol that
assists devices behind a NAT firewall or router with their packet
routing. STUN is commonly used in real-time voice, video, messag-
ing, and other interactive IP communication applications..
The protocol allows applications operating through a NAT to discov-
er the presence and specific type of NAT and obtain the mapped
(public) IP address (NAT address) and port number that the NAT
has allocated for the application's User Datagram Protocol (UDP)
connections to remote hosts. The protocol requires assistance from
a 3rd-party network server (STUN server).
STUN should be activated if an external SIP server cannot connect
to the Konftel 300IP behind a firewall NAT function and the SIP
server supports STUN. A suitable STUN server is usually provided
by the VoIP service provider.
Note: STUN might also be referred to as Session Traversal Utilities
for NAT.
The IP address or public name of the STUN server.
ICE (Interactive Connectivity Establishment), is a STUN addition
that provides various techniques to allow SIP-based VoIP devices to
successfully traverse the variety of firewalls that may exist between
the devices. The protocol provides a mechanism for both endpoints
to identify the most optimal path for the media traffic to follow.
TURN (Traversal Using Relay NAT ) TURN is an extension of the
STUN protocol that enables NAT traversal when both endpoints are
behind symmetric NAT. With TURN, media traffic for the session
will have to go to a relay server. Since relaying is expensive, in
terms of bandwidth that must be provided by the provider, and
additional delay for the media traffic, TURN is normally used as a
last resort when endpoints cannot communicate directly.
User authentication name on the TURN server.
The IP address or public name of the TURN server.
User authentication password on the TURN server.
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