Network Router User's Manual

LANCOM 821 ADSL/ISDN – LANCOM 1621 ADSL/ISDN – LANCOM 1711 VPN

 Chapter 1: Introduction

ISDN). Other models like LANCOM 1711 VPN are connected to the splitter

using a separate ADSL modem.

The model LANCOM 1711 VPN can also utilize other broadband con-

nections (e.g. cable modem) that offer a 10/100Base-Tx-Ethernet

connector over PPPoE, PPTP or plain Ethernet (with or without DHCP).

The models LANCOM 821 ADSL/ISDN and LANCOM 1621 ADSL/ISDN

can use this option, if the first LAN port is configured as WAN inter-

face.

ADSL- over-ISDN or ADSL-over-POTS?

ADSL can operate over modern ISDN telephone service as well as conven-

tional analog service (POTS – Plain Old Telephone Service).

There are, however, different technical specifications for the two telephone

systems. For this reason, devices in the LANCOM series are offered in two dif-

ferent versions: A version for ADSL-over-POTS and a version for ADSL-over-

ISDN.

You can determine which telephone system a device supports by looking at

the model description on the bottom of the device. The label containing the

device name also contains an additional code which stands for the telephone

system the device supports:

Code Supported telephone system

'Annex A' ADSL-over-POTS

'Annex B' ADSL-over-ISDN

Router

ADSL

modem

Internet

Splitter

Telephone

network

Splitter

ADSL provider

Switching node

DSL access

multiplexer

Subscriber