Spotel™ By Nicherons Canada
One Chunnel GSM VoIP Gateway
24
3.4.4 Codec Preference
Codec Preference
allows a user to select the codes to be used and its priority to be
selected for a voice call.
Click on the check box to enable a codec. Select a codec and then press the UP or
DOWN button to move the position of the codec on the codec list with a priority in
descending order.
Note: The voice code alaw and ulaw is G.711a and G.711u.
3.4.5 NAT Traversal
3.4.5.1 Signaling NAT Traversal
Signaling NAT traversal may be required if the Gateway is put behind a NAT (or
multiple NATs). Depending on your network environment and SIP Server capabilities,
this feature may or may not be turn on.
A
）
None
Select
None
to turn off this feature.
B
）
STUN (RFC 3489)
STUN
(
Simple Traversal of UDP (User Datagram Protocol) through NATs
(Network Address Translators)
) is a network protocol allowing a client behind a NAT
(or multiple NATs) to find out its public address, the type of NAT it is behind and the
internet-side port associated by the NAT with a particular local port.
Select
STUN (RFC 3489)
to use a STUN server for Signaling NAT Traversal. Enter
the IP Address or the domain name of the STUN server to be used.
C
）
Relay Proxy
Relay proxy
is a proprietary NAT traversal technology. Please consult your service
provider for more information.
