PLANET VIP-360PT - Manual (Page 37)

Echo Test Text Specify echo test text’s name.
Refresh Time Set expire time of IAX2 server register, you can set it between 60 and 3600
seconds.
Enable Register Start to register the IAX2 server or not by selecting it or not.
Enable G.729 Enable or disable code G.729 by selecting it or not
Stun Config
In this web page, you can config SIP STUN.
STUN:
By STUN server, the phone in private network could know the type of NAT and the NAT mapping IP and
port of SIP. The phone might register itself to SIP server with global IP and port to realize the device both
calling and being called in private network.