User's Manual
GXP2200 USER MANUAL Page 101 of 131
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/NETWORKSETTINGS
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.
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.