Asymmetric Digital Subscriber Line (ADSL)
Asymmetric digital subscriber line (ADSL) is a technology that
allows more data to be sent over existing copper telephone
lines. ADSL accomplishes this by using the portion of a
telephone line's bandwidth not utilized by voice, thereby
allowing for simultaneous voice and data transmission. Typical
remote access users receive much more information than they
send. The asymmetric nature of the ADSL connection fits well
with most Internet and remote business use. When receiving data,
ADSL supports data rates from 1.5 to 9 Mbps. When sending data,
ADSL supports data rates from 16 to 640 Kbps. Although ADSL
provides higher data transmission rates than do PSTN and ISDN
connections, the client computer can receive data at a faster
rate than it can send data.
LAN Interface or
Dial-up Interface
ADSL equipment can appear to Windows 2003 as either a LAN
interface or a dial-up interface. When an ADSL adapter appears
as a LAN interface, the ADSL connection operates in the same way
as a LAN connection to the Internet. When an ADSL adapter
appears as dial-up interface, ADSL provides a physical
connection and the individual packets are sent using
asynchronous transfer mode (ATM). An ATM adapter with an ADSL
port is installed in both the remote access client and remote
access server.