User guide

102
Voice over IP (VoIP)
VoIP Telephony via intranet with the Forum 523/524 offers the
following possibilities:
z Use of IP-based system telephones and of SIP telephones
connected to Cat5 twisted-pair ethernet cables
z Use of IP-based system telephones and of SIP telephones via
VPN, RAS, Branch or WLAN connections
z Using voice-data compression with compressing codecs, it is
also possible to make multiple IP-based telephone calls
simultaneously on a 64 kbit/s ISDN line
z Use of PC-supported system telephones (so-called
“Softphones”) without extra hardware costs
z Operation of SIP-capable telephony software (see also SIP
Telephony starting on page 117)
z TC system networking using Q.SIG-IP via VPN connections
(see also PBX Networking starting on page 152)
z Setting up a DECT over IP network lets you use existing
Ethernet cabling to set up a DECT network. The special DECT
base stations designed for this purpose, can be handled using
Forum 523/524’s Web interface (see DECT over IP
®
starting
on page 140).
Integrating voice and data communication within the Intranet can
provide savings possible and a range of new possibilities. However
joint usage of existing network infrastructure may also cause con-
flicts, with IP address configuration via DHCP for example (for
details see Start Procedure starting on page 131). You should
therefore always plan the use of VoIP in the Intranet together with
your network administrator. In order to avoid possible conflicts
please also note the information under Fundamentals starting on
page 107.