Grandstream GXP1450 - Manual (Page 32)

GXP1450 User Manual Page 31 of 38
Firmware 1.0.1.66 Last Updated: 05/2011
NAT Traversal This parameter activates the NAT traversal mechanism. It has options: No, STUN,
Keep-Alive, UPnP, Auto, VPN.
If selecting STUN and a STUN server is also specified, the phone performs
according to the STUN client specification. Using this mode, the embedded STUN
client detects if and what type of NAT/Firewall configuration is used. If the detected
NAT is a Full Cone, Restricted Cone, or a Port-Restricted Cone, the phone will use
its mapped public IP address and port in all of its SIP and SDP messages.
If selecting Keep-Alive with no specified STUN server, the GXP1450 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.
PUBLISH for Presence Enable Presence feature.
Proxy-Require SIP Extension to notify SIP server that the unit is behind the NAT/Firewall.
Voice Mail UserID When configured, user can access messages by pressing “MSG” button. This ID is
usually the VM portal access number.
Send DTMF This parameter specifies the mechanism to transmit DTMF digit. There are 3
supported modes: 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.
DTMF Payload Type Sends DTMF using RFC2833. The default is 101.
Early Dial Default is “No”. Use only if proxy supports 484 responses.
Dial Plan Prefix Sets the prefix added to each dialed number.