Grandstream GXP2130 Administration Guide - Manual (Page 34)

GXP2130/GXP2140/GXP2160
FIRMWARE VERSION 1.0.4.23 GXP2130/GXP2140/GXP2160
ADMINISTRATION GUIDE Page 32 of 81
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Backup IP 2.
If SIP server is configured as domain name, phone will not send DNS query,
but use “Primary IP” or “Backup IP x” to send SIP message if at least one of
them are not empty. Phone will try to use “Primary IP” first. After 3 tries without
any response, it will switch to “Backup IP x”, and then it will switch back to
“Primary IP” after 3 re-tries.
If SIP server is already an IP address, phone will use it directly even “User
Configured IP” is selected.
NAT Traversal
This parameter configures whether the NAT traversal mechanism is activated.
Users could select the mechanism from No, STUN, Keep-alive, UPnP, Auto or
VPN. The default setting is "No".
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 "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.
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.
Account x -> SIP Settings -> Basic Settings
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".
SIP Registration
Selects whether or not the phone will send SIP Register messages to the
proxy/server. The default setting is "Yes".
Unregister On Reboot
If set to "Yes", the SIP user's registration information will be cleared when the
phone reboots. The SIP Contact header will contain "*" to notify the server to
unbind the connection. The default setting is "No".
Register Expiration
Specifies the frequency (in minutes) in which the phone refreshes its
registration with the specified registrar. The default value is 60 minutes. The
maximum value is 64800 minutes (about 45 days).