LANCOM 1722 VoIP – LANCOM 1724 VoIP
Chapter 1: Introduction
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A maximum of 40 terminal devices connected over the ISDN network,
including ISDN and analog devices connected to an upstream ISDN PBX.
When connecting downstream PBXs to point-to-point lines, the number
of possible ISDN subscribers is determined by the length of the extension
number (DDI). In this case, all of the telephones and terminal equipment
connected to the PBX can be mapped with a single ISDN user entry.
SIP users
A maximum of 32 SIP terminal devices connected over LAN, WLAN and
DMZ and analog devices connected with an ATA.
The external paths of communication available to the users are known as
"lines". The LANCOM differentiates between the following lines:
ISDN
A connection to an ISDN NTBA over the TE interface. The NT interface can
additionally be used to connect ISDN terminal devices directly or via a
downstream ISDN PBX.
SIP lines
Maximum 16 SIP lines There are three different types of SIP line:
A "provider" line acts like a normal SIP account with a single tele-
phone number. The internal users can all make use this account for
making SIP calls, although only one call can be conducted at a time.
Depending on the provider services, these lines can be used to reach
subscribers in the provider networks, subscribers in other SIP net-
works (partner networks), or even land-line subscribers. Your own
availability at your own telephone number or even solely with an SIP
name over the Internet also differs from provider to provider.
A "trunk" line acts like an extended SIP account with a main external
telephone number and multiple extension numbers. Internal users use
this account in parallel and several calls can be made simultaneously
(until the maximum available bandwidth is exhausted).
As a "SIP gateway" line, the LANCOM VoIP Router provides a remote
SIP PBX with a transition to the local ISDN network. The SIP gateway
is registered at the SIP PBX with a single number, although several
calls can be conducted at once (until the maximum available band-
width is exhausted). The connection between the SIP PBX and the
LANCOM VoIP Router is normally established over a VPN connection.
SIP PBXs
