Grandstream GXP2200 User Manual - Manual (Page 121)

Firmware Version 1.0.3.26 GXP2200 USER MANUAL Page 120 of 159
ID display.
Tel URI
If the phone has an assigned PSTN telephone number, this field should
be set to "User=Phone". Then a "User=Phone" parameter will be
attached to the Request-Line and "TO" header in the SIP request to
indicate the E.164 number. If set to "Enable", "Tel:" will be used instead
of "SIP:" in the SIP request. The default setting is "Disable".
ACCOUNT/NETWORK SETTINGS
Outbound Proxy
IP address or Domain name of the Primary Outbound Proxy, Media
Gateway, or Session Border Controller. It's used by the phone for
Firewall or NAT penetration in different network environments. If a
symmetric NAT is detected, STUN will not work and ONLY an Outbound
Proxy can provide a solution.
Secondary Outbound Proxy
IP address or Domain name of the Secondary Outbound Proxy, Media
Gateway, or Session Border Controller. Secondary outbound proxy will
be used when the primary outbound proxy fails.
DNS Mode
This parameter controls how the Search Appliance looks up IP
addresses for hostnames. There are three modes: A Record, SRV,
NATPTR/SRV. The default setting is "A Record". If the user wishes to
locate the server by DNS SRV, the user may select "SRV" or
"NATPTR/SRV".
NAT Traversal
This parameter configures whether the NAT traversal mechanism is
activated. Users could select the mechanism from NAT NO, STUN,
Keep-alive, UPnP, Auto or VPN.
If set to "STUN" and STUN server is configured, the phone will route
according to the STUN server. If NAT type is Full Cone, Restricted Cone
or Port-Restricted Cone, the phone will try to use public IP addresses
and port number in all the SIP&SDP messages. The phone will send
empty SDP packet to the SIP server periodically to keep the NAT port
open if it is configured to be "Keep-alive". Configure this to be "NAT NO"
if an outbound proxy is used. "STUN" cannot be used if the detected
NAT is symmetric NAT. Set this to "VPN" if OpenVPN is used.
The default setting is "Keep-alive".
Proxy-Require
A SIP Extension to notify the SIP server that the phone is behind a
NAT/Firewall. Do not configure this parameter unless this feature is
supported on the SIP server.