Grandstream Networks DP752 Administration Manual page 49

Primary IP Specifies primary IP address where the base sends DNS query to, when "Use
Configured IP" is selected for DNS mode.
Backup IP 1 Specifies backup IP 1 address where the base sends DNS query to, when "Primary
IP" is not responding.
Backup IP 2 Specifies backup IP 2 address where the base sends DNS query to, when "Backup
IP 1" is not responding.
NAT Settings
NAT Traversal Enables/disables NAT traversal mechanism. If activated (by choosing "STUN") and
a STUN server is also specified (Maintenance → Network Settings → STUN
Settings); the base performs according to STUN client specification.
Under this mode, embedded STUN client will detect if and what type of firewall/NAT
is being used. If detected NAT is a Full Cone, Restricted Cone, or a Port-Restricted
Cone, the base will use its mapped public IP address and port in all of its SIP and
SDP messages.
periodically (every 20 seconds) send a blank UDP packet (with no payload data) to
SIP proxy to keep the "ping hole" on the NAT open.
Use NAT IP Defines NAT IP address used in SIP/SDP messages. It should only be used if
required by ITSP.
Proxy-Require Determines a SIP Extension to notify the SIP server that the base is behind a
NAT/Firewall.
SIP Settings
Basic Settings
SIP Transport Selects transport protocol for SIP packets; UDP or TCP or TLS. Make sure your
SIP server or network environment supports SIP over the selected transport
method. Default is UDP.
SIP Registration Controls whether to send SIP REGISTER messages to the proxy server. Device
may not be able to make/receives calls if disabled. Default is Yes.
Unregister on Controls whether to clear SIP user's information by sending un-register request to
Reboot the proxy server. The un-registration is performed by sending a REGISTER
message with "Contact" header set to * and Expires=0 parameters to the SIP
server. This will unregister all SIP accounts under concerned Profile. Default is Yes.
Add Auth Header Adds "Authentication" header with blank "nonce" attribute in the initial SIP
on Initial REGISTER REGISTER request. Default is No.
If NAT Traversal field is set to "Keep Alive", the base will
DP752/DP730/DP722 Administration Guide
Version 1.0.11.4
P a g e | 49