Internet
Frequently Asked Questions
211
Question: A SIP connection only passes unidirectional voice. What is the
reason?
You did not use the Forum 523/524 as internet router or the STUN server of
the SIP provider is unavailable. You did not use the Forum 523/524 as
internet router or the STUN server of the SIP provider is unavailable. You need
to activate the SIP support at your internet router, such as “SIP-ALG” or “Full
Cone NAT” functions. You can also use the Forum 523/524 for internet
access. Correct the STUN setting in the
Telephony
:
Trunks
:
SIP Provider
menu.
Question: Is it possible to use Q.SIG-IP / SIP tie line connections via an
Internet access with dynamic IP address?
No. Q.SIG-IP / SIP tie line connections require (as with IP system telephones
and SIP terminals) a fixed IP assignment and a connection without NAT for
technical and security reasons. It is possible to tunnel a Q.SIG-IP / SIP tie line
connection through a VPN connection. A VPN connection offers the possibility
to determine the peer’s IP address with a DynDNS service during connection
setup. VPN and DynDNS can be realized with external servers or routers also.