User guide

SIP Telephony 121
Voice over IP (VoIP)
subscribers, this setting is frequently located under “SIP
Server” or “SIP Settings” with the terms “Domain”, “Server IP”
and “Server Port”.
z The “REGISTER” SIP message must contain a valid user name
and the appropriate password (the User name and Password
fields in the Configurator under User Manager: User). For
SIP subscribers, this setting is frequently located under “SIP
User Settings” or “SIP Account” with the terms “Authorization
User” and “Password”.
z The “REGISTER” SIP message also contains a SIP-URI in the
spelling for e-mail addresses, for example
"Displayname" <sip:123@192.168.99.254> . The text portion
of the SIP-URI (“Display Name”) is not evaluated at log-on
from the Forum 523/524. The series of characters before “@”
is the “User Name” or “SIP Username”. The internal call
number of the user must always be used here (the Ph.No.
field in the Configurator under User Manager: User). The
series of characters after “@” is the “Domain Name” or the
“SIP Domain”. The IP address of the Forum 523/524 must
always be used here.
z A STUN server (Simple Traversal of UDP over NAT) or a SIP
proxy is not required because internal SIP subscribers on the
LAN are directly connected to the Forum 523/524. Switch
these functions off if possible.
z With a SIP terminal, you can enter an international phone
number with a leading plus. When you enter a call number in
the E.123 format, the plus char is substituted by the “00”
number sequence and the immediate line seizure via the
standard route is activated for the call. If you prefer to dial in
this number format, you should activate the international call
number conversion (see E.164 conversion starting on
page 165).
Features
SIP subscribers can establish connections to all other terminals
and trunks. The SIP protocol generally works with block dialling.
This is why the selected call number is only activated after an
internal clock has expired or activated immediately via the hash
key (“#”) when dialling. This is why code number procedures