LANCOM 1722 VoIP – LANCOM 1723 VoIP – LANCOM 1724 VoIP – LANCOM 1823 VoIP
Chapter 1: Introduction
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1 Introduction
LANCOM VoIP Routers are fully functional routers with an integrated firewall
to provide local networks with secure access to the Internet.
With the VPN option included, these devices work as powerful Dynamic VPN
gateways for external locations or mobile users.
Along with the ADSL connection, these devices also feature ISDN connections,
and some feature analog telephone connections. An ISDN line can be used to
backup the WAN connection, for remote management of the router, as a basis
for office communications via LANCAPI, and for establishing Dynamic VPN
connections to external locations that use dynamic IP addresses.
By using the Voice over IP function, these devices can transfer voice data over
broadband Internet as well as over ISDN and analog telephone connections.
LANCOM 1823
VoIP only
LANCOM Wireless Routers and LANCOM Access Points can be oper-
ated either as self-sufficient access points with their own configura-
tion (WLAN modules in "Access Point mode") or as components in a
WLAN infrastructure, which is controlled from a central WLAN Con-
troller ("managed mode"). Please observe the corresponding notices
in this documentation.
LANCOM VoIP routers can be upgraded with powerful controls over Internet
access with the LANCOM Content Filter Option. This intelligent high-end solu-
tion uses a database-supported web filtering technology that works with pro-
files to control access rights and that also offers practical functions such as
overrides. A system requirement for operating the content filter is LCOS 8.0,
the operating system available for free download from LANCOM.
1.1
How do ADSL and ADSL 2+ work?
ADSL (Asymmetric Digital Subscriber Line) is currently the most common tech-
nology for broadband Internet connections. Standard and almost ubiquitous
telephone lines (analog or DSL) are the basis for DSL data transfer to the near-
est telephone exchange. From here, the data is passed directly on to the Inter-
net over high-speed connections.
The asymmetric DSL variant ADSL was developed for applications where users
receive large amounts of data but transmit only small amounts, such as when
surfing in the WWW. ADSL subscribers can receive data at up to 8 Mbps
("downstream") and transmit at up to 800 kbps ("upstream"). ADSL providers
are able to reduce these maximum rates as they please.
