While the information in this manual has been compiled with great care, it may not be deemed an assurance of product
characteristics. LANCOM Systems shall be liable only to the degree specified in the terms of sale and delivery.
The reproduction and distribution of the documentation and software included with this product is subject to written permission by LANCOM Systems. We reserve the right to make any alterations that arise as the result of technical development.
Trad ema rks
®
Windows
, Windows XP® and Microsoft® are registered trademarks of Microsoft, Corp.
The LANCOM Systems logo and the name LANCOM are registered trademarks of LANCOM Systems GmbH. All other names
mentioned may be trademarks or registered trademarks of their respective owners.
Subject to change without notice. No liability for technical errors or omissions.
This product includes software developed by the OpenSSL Project for use in the OpenSSL Toolkit http://www.openssl.org/
With the LANCOM you have chosen a powerful router that possesses integrated DSL respectively ADSL and ISDN interfaces by default as well as an
integrated 4-port switch. With this router you can simply and comfortably
connect individual PCs or whole local networks to the high-speed Internet.
Security settings
For a carefree use of your device, we recommend to carry out all security settings (e.g. Firewall, encryption, access protection, charge lock), which are not
already activated at the time of purchase of your device. The LANconfig wizard
’Check Security Settings’ will support you accomplishing this. Further information regarding this topic can be found in chapter “Security settings” on
page 66.
We ask you additionally to inform you about technical developments and
actual hints to your product on our Web page www.lancom.de
load new software versions if necessary.
User manual and reference manual
The documentation of your device consists of two parts: the user manual and
the reference manual.
You are now reading the user manual. It contains all information you need to
start your LANCOM. It also contains the most important technical specification for the device.
The reference manual can be found on the CD as an Acrobat (PDF) document.
It is designed as a supplement to the user manual and goes into detail on topics that apply to a variety of devices. These include for example:
Systems design of the LCOS operating system
Configuration
Management
Diagnosis
Security
Routing and WAN functions
Firewall
Quality of Service (QoS)
Virtual Private Networks (VPN)
The sections of the documentation that refer only to a range of models are
marked either in the corresponding text itself or with appropriate comments
placed beside the text.
In the other parts of the documentation, all described models have been classified under the general term LANCOM.
This documentation was compiled …
...by several members of our staff from a variety of departments in order to
ensure you the best possible support when using your LANCOM product.
In case you encounter any errors, or just want to issue critics or enhancements, please do not hesitate to send an email directly to:
info@lancom.de
Our online services ( www.lancom.de) are available to you around the
clock should you have any queries regarding the topics discussed in
this manual or require any further support. In addition support from
LANCOM Systems is also available to you. Telephone numbers and
The models LANCOM 821 ADSL/ISDN, LANCOM 1621 ADSL/ISDN and
LANCOM 1711 VPN are fully-featured routers that therefore also can be used
in combination with the integrated firewall for providing secure Internet
access to a complete local network (LAN).
The VPN option, which is either integrated already or can be activated subsquently, enables the LANCOM 1621 ADSL/ISDN and LANCOM 1711 VPN to
act as powerful Dynamic VPN gateways for external offices or mobile users.
The LANCOM models offer each a DSL or ADSL connector and also an ISDN
connector. The ISDN line can be used as back-up for the DSL connection, for
remote management of the router, as basis for the office communication via
LANCAPI or for establishing VPN connections to remote sites with dynamic IP
addresses.
1.1How does ADSL work?
Chapter 1: Introduction
EN
For LANCOM 821
ADSL/ISDN and
LANCOM 1621
ADSL/ISDN only
Since the late 1980s, scientists have been working on the idea of using conventional telephone lines for video and multimedia applications.
High speed via standard telephone lines
Their approach was based on the use of telephone lines only for the distance
between the subscriber and the next local exchange. From the switching
center, the data is then transferred via high-speed connections to the desired
destination or target network (i.e. the Internet). This minimization of the telephone line distance used permits considerably higher transfer rates than
would be possible when relying solely on the telephone network.
LAN
ADSL connection via
telephone line
LANCOM
Internet
Local exchange (central office)
All DSL technologies, of which ADSL is the most common, are based on this
concept. Thanks to their high transfer speeds, DSL connections are well-suited
for Internet access.
The ADSL version of DSL was designed for applications in which the user
receives high volumes of data but only transmits relatively small volumes. A
typical example for this would be access to the world wide web (www). Only
a few commands (mouse clicks) are required to initiate the download of very
large volumes of data such as graphics, texts, audio or video files. The user
typically only sends very small amounts of data across the Internet connec-
EN
tion.
With an ADSL connection, a user can download at up to 8 Mbps (“downstream”) and upload at up to 800 Kbps (“upstream”). These maximum rates
can be reduced as required by the ADSL provider. A typical access plan might
specify, for example, 768 Kbps download and 128 Kbps upload speed.
All services via a single cable—thanks to the splitter
With ADSL, all traditional telephony applications (telephone, fax, answering
machine, PBX) can still be used without restrictions. So-called splitters make
this possible. Splitters are devices that separate the telephone line's “voice
frequencies” from the “data frequencies” and ensure that the signals are forwarded to the appropriate networks. Voice signals are passed on to the existing telephone network, while data signals are forwarded to their destinations
(i.e. Internet providers) via high-bandwidth network connections.
A splitter is also used at the subscriber end to permit ADSL modems/routers
and conventional telephone equipment to be used at the same time.
10
Telephone
network
Internet
Switching node
DSL access
multiplexer
ADSL provider
Splitter
Router with integrated
Splitter
ADSL modem
Tel ep hon e
Subscriber
In some models (like in the picture above) the ADSL modem is integrated
directly in the router (e.g. LANCOM 821 ADSL/ISDN and LANCOM 1621 ADSL/
ISDN). Other models like LANCOM 1711 VPN are connected to the splitter
using a separate ADSL modem.
Telephone
network
Internet
Switching node
DSL access
multiplexer
ADSL provider
Splitter
Splitter
ADSL
modem
Tel ep hon e
Router
Subscriber
The model LANCOM 1711 VPN can also utilize other broadband connections (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 interface.
ADSL-over- ISDN or ADSL-over-POTS?
ADSL can operate over modern ISDN telephone service as well as conventional 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 different versions: A version for ADSL-over-POTS and a version for ADSL-overISDN.
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:
An 'Annex A' type LANCOM can only be used with ADSL-over-POTS service.
Similarly, an 'Annex B' device can only be used with ADSL-over- ISDN service.
Retrofitting a device to function with a different telephone system is not possible.
ADSL-over-ISDN connections also exist that do not operate in conjunction
with ISDN, but which use a conventional analog telephone connection. A
prominent example would be Deutsche Telekom’s T-DSL service.
EN
For LANCOM 1711
VPN and LANCOM
1621 ADSL/ISDN
1.2Which use does VPN offer?
A VPN (Virtual Private Network) can be used to set up cost- effective, public
IP networks, for example via the ultimate network: the Internet.
The models LANCOM 1621 ADSL/ISDN and LANCOM 1711 VPN are
equipped with 5 channels by default. The additional LANCOM VPN
Option can extend VPN support to 25 active tunnels. The VPN-25
Option also activates the VPN hardware accelerator in the LANCOM
1711 VPN.
While this may sound unspectacular at first, in practice it has profound effects.
To illustrate this, let's first look at a typical corporate network without VPN
technology. In the second step, we will see how this network can be optimized
by the deployment of VPN.
First, let's have a look at a typical network structure that can be found in this
form or similar forms in many companies:
LAN
Head Office
LAN
Subsidiary
Workstation in remote
access, e.g. homework
Internet
The corporate network is based on the internal network (LAN) in the headquarters. This LAN is connected to the outside world in three ways:
A subsidiary is connected to the LAN, typically using a leased line.
PCs dial into the central network via modem or ISDN connections (Remote
Access Service – RAS).
The central LAN has a connection to the Internet so that its users can
access the Web, and send and receive e-mail.
All connections to the outside world are based on dedicated lines, i.e.
switched or leased lines. Dedicated lines are very reliable and secure. On the
other hand, they involve high costs. In general, the costs for dedicated lines
are dependent on the distance. Especially in the case of long-distance connections, keeping an eye out of cost-effective alternatives can be worthwhile.
EN
The appropriate hardware must be available in the headquarters for every
type of required connection (analog dial-up, ISDN, leased lines). In addition
to the original investment costs, ongoing costs are also incurred for the
administration and maintenance of this equipment.
Networking via the Internet
The following structure results when using the Internet instead of direct connections :
EN
LAN
Head Office
LAN
Subsidiary
Internet
Workstation in remote
access
All participants have fixed or dial-up connections to the Internet. Expensive
dedicated lines are no longer needed.
All that is required is the Internet connection of the LAN in the headquar-
ters. Special switching devices or routers for dedicated lines to individual
participants are superfluous.
The subsidiary also has its own connection to the Internet.
The RAS PCs connect to the headquarters LAN via the Internet.
14
The Internet is available virtually everywhere and typically has low access
costs. Significant savings can thus be achieved in relation to switched or dedicated connections, especially over long distances.
The physical connection no longer exists directly between two participants;
instead, the participants rely on their connection to the Internet. The access
technology used is not relevant in this case: ideally is the use of broadband
technologies such as DSL (Digital Subscriber Line). But also a conventional
ISDN line can be used.
The technologies of the individual participants do not have to be compatible
to one another, as would be the case for conventional direct connections. A
single Internet access can be used to establish multiple simultaneous logical
connections to a variety of remote stations.
The resulting savings and high flexibility makes the Internet (or any other IP
network) an outstanding backbone for a corporate network.
1.3Firewall
The integrated Stateful Inspection Firewall ensures an effective protection
against undesired intrusion in your network by permitting only incoming data
traffic as reaction to outgoing data traffic. The router’s IP masquerading function hides all workstations of the LAN behind a single public IP address. The
actual identities (IP addresses) of the individual workstations remain concealed. Firewall filters of the router permit specific IP addresses, protocols and
ports to be blocked. With MAC address filters it is also possible to specifically
monitor the access of workstations in the LAN to the IP routing function of the
device.
Chapter 1: Introduction
EN
LAN
Internet
Firewall
LANCOM
Further important features of the Firewall are
Intrusion Detection
Break-in attempts into the local network or on the central Firewall are recognized, repelled and logged by the Intrusion Detection system (IDS) of
the LANCOM DSL. Thereby it can be selected between logging within the
device, email notification, SNMP trap or SYSLOG alarms.
Attacks from the Internet can be break- in attempts as well as attacks with
the aim of blocking the accessibility and functionality of individual
services. Therefore a LANCOM DSL is equipped with appropriate protective mechanisms, which recognize well-known hacker attacks and which
guarantee the functionality.
Quality-of-Service / Traffic management
EN
The generic term Quality-of-Service (brief: QoS) summarizes the functions
of the LANCOM which guarantee certain service qualities. The advantage
is that the QoS functions can take place by means of the existing powerful
classification methods of the Firewall (e.g. limitation of subnetworks,
single workstations or certain services).
Guaranteed minimum bandwidths give priority to enterprise critical applications, VoIP PBX installations or certain user groups.
More details about the function of the Stateful Inspection Firewall of
your LANCOM can be found in the reference manual on the LANCOM
CD.
1.4What does a router do?
16
The following sections describe the functionality of routers in general.
The functions supported by your device are listed in the table “What
can your LANCOM do?” on page 18.
Routers connect LANs at different locations and individual PCs to form a Wide
Area Network (WAN). With the appropriate rights, any computer in this WAN
can access other computers and services of the complete WAN (as with 'PC 1'
accessing 'Server A' in the remote LAN in the diagram).
Connecting a LAN to the Internet does not technically differ from coupling
two LANs. The only difference is that it is not just a handful of computers
behind the Internet provider's router. Instead, it is the net of the networks the public Internet.
1.4.1Bridgehead to the WAN
All routers have at least two connections:
at least one for the LAN
at least one for WAN connections
In addition to LAN connectivity (10/100 Mbps Ethernet), several models also
offer an integrated switch. For the connecting to the WAN, the routers use
ISDN, xDSL/cable or ADSL connectors. Several devices contain additionally a
wireless network card and can thus integrate also stations of WLANs (Wireless
LANs) into the routing.
The router's task is to transfer data from the local network to the target network via a suitable WAN connection. Data is also transferred from the WAN
to the desired recipients in the LAN.
1.4.2Areas of deployment for routers
Chapter 1: Introduction
EN
Not possible with
all LANCOM
devices.
Routers are mainly used for the following applications:
Internet access for a LAN (e.g. via DSL or ISDN)
The Internet consists of countless large and small networks that are interconnected into the world's largest WAN via routers. The router links all the
workstation computers on your local area network to the global Internet.
Security functions such as IP masquerading protect your LAN against
unauthorized access from outside.
LAN to LAN coupling (via VPN or ISDN)
LAN to LAN coupling links individual LANs to form one large network,
even if this means crossing continents. A typical example: A branch office
is to be connected to the LAN of the headquarters. In principle, you can
connect LANs in two ways:
High-speed coupling via VPN
The fastest and most economical LAN to LAN links are possible with
VPN (Virtual Private Network) technology, as VPN uses the Internet as
the basis for its communications. The fast xDSL connection of the
router comes into its own here. The precondition: a VPN gateway with
access to the Internet is required on either side of the network interconnection.
VPN tunnel via the
Internet
EN
VPN gateways
Conventional via ISDN
Without VPN, a LAN to LAN interconnection can alternatively be realized via ISDN. In this case, an intelligent line management and
sophisticated filter mechanisms keeps connection costs low.
Remote access to the company network (via VPN or ISDN)
The work of many office workers in modern organizations is less and less
dependent on any definite location—the most important factor here is
unimpaired access to shared and freely available information.
Remote Access Service (RAS) is the magic word here. Employees working
from home or field staff can dial into the company network via VPN or
ISDN. When working with remote access via ISDN, the router protects the
company network: the call back function only grants access to known and
registered users.
1.5What can your LANCOM do?
The following table contains a direct comparison of the properties and functions of your devices with other models:
Firewall filters for a selective locking of IP addresses, protocols and ports
MAC address filter control e.g. the access of LAN workstations to IP routing
functions
EN
Configuration protection to block “brute force attacks“
Configuration
Configuration with LANconfig or with web browser, additionally terminal
mode for Telnet or other terminal programs, SNMP interface and TFTP server
function.
Remote configuration via ISDN (with ISDN-PPP connections e.g. via Windows network and dial-up connections)
Serial configuration interface
Callback function with PPP authentication mechanisms for restriction to
fixed ISDN telephone numbers
FirmSafe with firmware versions for absolutely secure software upgrades
Optional software extensions
ISDN leased line option
LANCOM VPN Option with 25 active tunnels for protection of network couplings
This chapter will assist you to quickly install hardware and software. First,
check the package contents and system requirements. The device can be
installed and configured quickly and easily if all prerequisites are fulfilled.
2.1Package contents
Chapter 2: Installation
Please check the package contents for completeness before starting the
installation. In addition to the device itself, the package should contain the
following accessories:
Power adapter
LAN connector cable (green plugs)
WAN connector cable (dark blue plugs)
ADSL connector cable (transparent plugs)
ISDN connector cable (light blue plugs)
Connector cable for the configuration interface
LANCOM CD
Printed documentation
If anything is missing, please contact your retailer or the address stated on the
delivery slip of the unit.
2.2System preconditions
EN
DSL
ADSL/ISDN
LANCOM 821
ADSL/ISDN
LANCOM 1621
LANCOM 1711
Computers that connect to a LANCOM must meet the following minimum
requirements:
Operating system that supports TCP/IP, e.g. Windows XP, Windows Mil-
lennium Edition (Me), Windows 2000, Windows 98, Windows 95, Windows NT, Linux, BSD Unix, Apple Mac OS, OS/2, BeOS.
The LANtools and the LANCAPI functions also require a Windows
operating system. A web browser is required for access to WEBconfig.
2.3Introducing LANCOM
This section introduces your device. We will give you an overview of all status
displays, connections and switches.
EN
While the information in this section is useful for the installation of the
device, it is not absolutely essential. You may therefore skip this section for the time being and go straight forward to “Hardware installation” on page 28.
2.3.1Status displays
The front and the rear panels (LANCOM 821 ADSL/ISDN) of the unit feature a
series of light emitting diodes (LEDs) that provide information on the status of
the device. On the LANCOM 1621 ADSL/ISDN a two-lined display additionally
shows information on the status.
LANCOM 821 ADSL/
ISDN and LANCOM
1621 ADSL/ISDN
LANCOM 1711 VPN
22
Front side
The various LANCOM models have different numbers of indicators on the front
panel depending on their functionality.
The two LEDs on the top panel provide a convenient overview of the most
important status information, especially when the device is installed vertically.
Power
Power
Online
Meanings of the LEDs
In the following sections we will use different terms to describe the behaviour
of the LEDs:
Blinking means, that the LED is switched on or off at regular intervals in
the respective indicated colour.
Flashing means, that the LED lights up very briefly in the respective col-
our and stay then clearly longer (approximately 10x longer) switched off.
Inverse flashing means the opposite. The LED lights permanently in the
respective colour and is only briefly interrupted.
Flickering means, that the LED is switched on and off in irregular inter-
vals.
This LED indicates that the device is operational. After the device has been
switched on, it will flash green for the duration of the self-test. After the selftest, either an error is output by a flashing red light code or the device starts
and the LED remains lit green.
EN
offDevice off
greenblinkingSelf-test when powering up
greenconstantly onDevice ready for use
red/
green
redblinkingTime or connect-charge reached
blinking alternatelyDevice insecure: configuration password not assigned
The power LED flashes red/green in alternation until a configuration
password has been specified. Without a configuration password, the
configuration data of the LANCOM is insecure. Under normal circumstances, you would assign a configuration password during the basic
configuration (see instructions in the following chapter). For information about a later assignment of the configuration password see the
section “Security settings” on page 66.
EN
Flashing Power LED but no connection?
There's no need to worry if the Power LED blinks red and you can no
LANCOM
Systems
longer connect to the WAN. This simply indicates that a preset time or
connect-charge limit has been reached. There are three methods
available for unlocking:
Reset connect charge protection.
Increase the limit that has been reached.
Signal for reached time
or connect-charge
limit
Completely deactivate the lock that has been triggered (set limit
to '0').
If a time or connect charge limit has been reached, you will be notified in LANmonitor. To
reset the connect charge protection, select Reset Charge and Time Limits in the context
menu (right mouse click). You can configure the connect charge settings in LANconfig under
Management /Costs (you will only be able to access this configuration if 'Complete con-
figuration display' is selected under View / Options…).
You will find the connect charge protection reset in WEBconfig and all parameters under
Expert Configuration /Setup / Charges-module.
Online
The Online LED indicates the overall status of all WAN ports:
offNo active connection
greenflashingEstablishing first connection
greeninverse flashingEstablishing further connection
greenconstantly onAt least one connection established
redconstantly onError establishing the previous connection