ATL Telecom IP300S - Manual (Page 89)

IP SIP Phone v2 User’s Guide Mar. 2005
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Note, this diagnosis utilize STUN server, you must have assigned a valid/viable STUN
server first.
„ Static NAT IP: Fill in the acquired NAT IP from network administrator, such as
218.81.107.51 mentioned above.
„ UDP traversal: Static NAT IP/UDP Map
Note
, if your NAT equipped with no fixed IP, such as those NATs dial into WAN by
PPPoE, then you must synchronize the NAT IP currently set into IP SIP Phone
whenever your NAT IP changed (such as NAT re-dialup). By default, the system will
regularly (every 10 minutes) auto-detect the NAT IP (if t 『 』 he STUN server set a
valid and viable server 『 ) and notify you on the
IP SIP Phone』 status page
whenever it determines a mismatch between the static NAT IP you configured and
the one it auto-discovered by STUN protocol.
『 Alternatively, you may enable Auto 』 Detect & Update Static NAT IP by STUN to
auto- 『 』 refresh the newly changed NAT IP into Static NAT IP field whenever it
detects an inconsistency.
13.2.2. NAT Traversal by STUN
Setting up the NAT router is impossible in many cases, and new equipment may be too
expensive. For these environments, "Simple Traversal of UDP Through NATs" (STUN) has come
to rescue. To enable STUN, you must acquire the IP of your served STUN server and diagnose
your NAT to see if STUN is viable.
z To determine whether you are currently NATed or behind a firewall:
„ STUN server: configure your STUN server, such as “qt.com” (IP SIP Phone will
try to locate the STUN server of “qt.com” domain via DNS SRV query
(_stun._udp.qt.com) or you may explicitly specify the STUN server as
“STUN.qt.com” or 61.222.26.124. You can enter both dotted IP and DNS record.
„ Click 『Set and Diagnose NAT』to detect your NAT type. If the diagnosis is one
of the following, you could consider to enable STUN as a way to traverse NAT;
otherwise you should adopt option 1-『Stati
』 c NAT Route .
(a) Public internet (neither NAT nor Firewall is involved).
(b) Symmetric UDP Firewall
(c) Full cone NAT
(d) Restricted cone NAT
(e) Port restricted cone NAT.
Note: The NAT bundled with Windows 2000/XP/2003 can NOT be traversed by STUN
protocol, even though it may wrongly detected by STUN as Port-restricted NAT.