User's Manual

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GXP17xx Administration Guide
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
Determines 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
Determines 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).
Reregister Before
Expiration
Specifies the time frequency (in seconds) that the phone sends
re-registration request before the Register Expiration. The default value is 0.
Local SIP Port
Defines the local SIP port used to listen and transmit. The default value is
5060 for Account 1, 5062 for Account 2, 5064 for Account 3, 5066 for Account
4, 5068 for Account 5, 5070 for Account 6. The valid range is from 1 to 65535.
SIP Registration Failure
Retry Wait Time
Specifies the interval to retry registration if the process is failed. The valid
range is 1 to 3600. The default value is 20 seconds.
SIP T1 Timeout
SIP T1 Timeout is an estimate of the round trip time of transactions between
a client and server. If no response is received the timeout is increased, and
request re-transmit retries would continue until a maximum amount of time
define by T2. The default setting is 0.5 seconds.
SIP T2 Timeout
SIP T2 Timeout is the maximum retransmit time of any SIP request
messages (excluding the INVITE message). The re-transmitting and doubling
of T1 continues until it reaches the T2 value. The default setting is 4 seconds.