A Digital Subscriber Line
is a device used to connect a computer
to a telephone circuit that has Digital Subscriber Line
service configured. Like other modems
, it is a type of transceiver
. It is also called a DSL Transceiver
Transceiver Unit-Remote). The acronym NTBBA
, which stands for network termination broad band adapter
, is also common in some countries.
Some DSL modems also manage the connection and sharing of the DSL service in a network, in this case, the unit is termed a DSL router
or residential gateway
. DSL routers have a component that performs framing, while other components perform Asynchronous Transfer Mode Segmentation and Reassembly
, IEEE 802.1D
bridging and/or IP routing (including network address translation
). Typical user interfaces are Ethernet
and Universal Serial Bus
(USB). Although a DSL modem working as a bridge
does not need an IP address
, it may have one assigned for management purposes.
Compared to voice-band modem
A DSL modem modulates high-frequency tones for transmission to a Digital Subscriber Line Access Multiplexer
(DSLAM), and receives and demodulates them from the DSLAM. It serves fundamentally the same purpose as the voice-band
modem that was a mainstay in the late 20th century, but differs from it in important ways.
- DSL modems transfer data at a rate which is typically 10 to 20 times that of a voice-band modem.
- A single telephone line can be used for simultaneous voice and data with a......