LANCOM 1722 VoIP – LANCOM 1724 VoIP
Chapter 1: Introduction
24
EN
The great advantage with this two-stage registration comes to bear in the
backup event: If the connection to an upstream SIP PBX is not available, the
SIP proxy can handle the user who is registered upstream as a local user and
can then direct the calls over alternative lines.
Registration at the LANCOM VoIP Router (local registration)
For local registration at the LANCOM, it is initially sufficient for the user to
send a valid VoIP domain to the SIP proxy. The internal VoIP domains of the
LANCOM VoIP Router are valid, as are all domains entered in a SIP line.
For SIP terminal devices in the LAN (SIP telephone or SIP softphone), the
domain is entered in the configuration. There is no need for an entry as a
SIP user in the configuration of the LANCOM. This variant is known as
"automatic registration".
The domain cannot be entered into ISDN terminal equipment; instead,
ISDN users have to be registered in the LANCOM configuration with a cor-
responding entry as an ISDN user (
→
Dynamic ISDN user registration at
point-to-point lines).
To prevent unknown subscribers from registering, authentication at the
SIP proxy can be set as a prerequisite to local registration (local authenti-
cation). In this case, an entry as a SIP or ISDN user in the LANCOM con-
figuration is essential.
Automatic registration without entering a password is restricted to
the SIP users in the LAN. SIP users in the WAN require an appropriate
user entry and authentication by password.
Registration at an upstream SIP PBX (upstream registration)
Generally, authentication by user and password is always required for regis-
tration at a SIP PBX. There are two possible ways of transmitting the authen-
tication data to the SIP PBX:
All SIP and ISDN users at the LANCOM VoIP Router end use the same
shared access information. In this case, only the VoIP domain for the SIP
PBX and the appropriate user ID are entered into the SIP terminal device.
For ISDN users, the VoIP domain of the SIP PBX is entered into the
LANCOM as an ISDN user. The SIP proxy recognizes the request for regis-
tration at the upstream SIP PBX if the domain communicated from the cli-
ent agrees with a domain entered into the SIP PBX line. The proxy then
forwards the registration data together with the shared password to the
SIP PBX.
