User manual

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NAT Traversal
This parameter defines whether the GXP-2000 NAT traversal
mechanism will be activated or not. If activated (by choosing “Yes”)
and a STUN server is also specified, then the GXP-2000 will behave
according to the STUN client specification. Under this mode, the
embedded STUN client inside the GXP-2000 will attempt to detect if
and what type of firewall/NAT it is sitting behind through
communication with the specified STUN server. If the detected NAT is
a Full Cone, Restricted Cone, or a Port-Restricted Cone, the GXP-2000
will attempt to use its mapped public IP address and port in all of its SIP
and SDP messages. If the NAT Traversal field is set to “Yes” with no
specified STUN server, the GXP-2000 will periodically (every 20
seconds or so) send a blank UDP packet (with no payload data) to the
SIP server to keep the “hole” on the NAT open.
Subscribe for
MWI:
Default is No. When set to “Yes” a SUBSCRIBE for Message Waiting
Indication will be sent periodically.
Proxy-Require
SIP Extension to notify SIP server that the unit is behind the
NAT/Firewall.
Voice Mail User ID
When configured, user will be able to dial voice mail server by pressing
“MSG” button.
Send DTMF
This parameter specifies the mechanism to transmit DTMF digit. There
are 3 modes supported: in audio which means DTMF is combined in
audio signal (not very reliable with low-bit-rate codec), via RTP
(RFC2833), or via SIP INFO.
Early Dial
Default is No. Use only if proxy supports 484 response.
Dial Plan Prefix
Sets the prefix added to each dialed number.
Enable Call
Features
Default is No. If set to Yes, Call transfer, Call Forwarding & Do-Not-
Disturb are supported locally.
Disable Missed-Call
Default is No. If set to Yes, missed calls will not be recorded for your
review.
Session Expiration
Grandstream implemented SIP Session Timer. The session timer
extension enables SIP sessions to be periodically “refreshed” via a SIP
request (UPDATE, or re-INVITE. Once the session interval expires, if
there is no refresh via a UPDATE or re-INVITE message, the session
will be terminated.
Session Expiration is the time (in seconds) at which the session is
considered timed out, if no successful session refresh transaction occurs
beforehand. The default value is 180 seconds.