DSL-200 ADSL USB Modem User’s Guide
4
ADSL Service
In order to use the Modem you must first have ADSL service established with a DSL service
provider.
There are four standards used for ADSL connections known as ANSI T1.413 issue 2, G.Lite,
G.dmt and G.hs. The standards differ somewhat as to data transfer speed or bit rate. For user
convenience, the Modem supports the G.hs Auto-handshake ADSL standard. This allows the
Modem to operate with either type of connection.
Network Protocol and the Software Driver
The protocol used for your ADSL service will determine the particular software driver to be
installed. You will need to select one driver to operate the Modem. Ask your DSL service provider
to assist you in selecting either the LAN (Local Area Network) or WAN (Wide Area Network)
driver to operate the Modem.
If your ADSL service uses PPP (Point-to-Point Protocol) to establish the connection, you will
install the WAN driver. Using a PPP connection will be familiar to anyone who has used a
conventional dial-up analog modem for Internet connection. PPP is used to verify the user’s
identity and to control access to the network. A PPP session requires that a user name and
password be given before gaining access to network services. PPP sessions are ended when you
log-off and terminate your connection to the service provider’s network. Specifically, if your
ADSL service uses the protocol defined by RFC 2364, PPP over ATM Adaptation Layer 5, or RFC
2516, PPP over Ethernet, install the WAN driver.
If the protocol used for your ADSL service is defined by RFC 1483, Multiprotocol Encapsulation
over ATM Adaptation Layer 5 (Bridged Ethernet), then you will need to install the LAN driver.
LAN driver users may be required to manually configure your IP settings. Your DSL service
provider will tell you if you need to configure your PCs IP settings.
The drivers are fundamentally different in the way they relate to operating system of the computer.
The computer/Modem relationship can be summarized as follows:
WAN driver – To your computer, the Modem appears as a conventional dial-up modem device,
the Modem employs the same Microsoft Dial-Up Networking software. There is no actual
dialing or any activity in the voice band frequencies on the telephone line, but you must still
provide a user name and password to log-on.
LAN driver – To your computer, the Modem appears as an Ethernet device.
Connection is automatic, similar to a connection to an Ethernet device.
Encapsulation Method
It may be necessary to use an encapsulation method that is different from the default method. The
protocol used for your connection, and thus the driver you use will determine which encapsulation
method is used. If your DSL service provider does not specify, use the default encapsulation
method.
Modulation Technique
It may be necessary to use a modulation method that is different from the default method. If your
DSL service provider does not specify, use the default modulation method called Multimode.
