|
DSL |
(Digital Subscriber
Line) – DSL is the
optimal connection for
today's small-to-medium
business because of its
speed and flexibility.
DSL is a high-speed
transmission technology
using existing copper
wiring; this allows
high-speed data
communication. It is
popular because the
copper wire eliminates
the cost of a local loop
for connection. xDSL
refers to different
variations of DSL, such
as IDSL, ADSL, HDSL, and
RADSL. |
|
ATM |
Asynchronous Transfer
Mode. A high-speed
network protocol
especially good for real
time voice and video.
DSL lines normally use
ATM as the underlying
data-transport protocol
beneath TCP/IP. |
|
CLEC |
Competitive Local
Exchange Carrier. |
|
Central
Office |
A circuit
switch that terminates
all the local access
lines in a particular
geographic serving area;
a physical building
where the local
switching equipment is
found. DSL lines running
from a subscriber's home
connect at their serving
Central Office (CO). |
|
CPE |
Customer
Premise (or Provided)
Equipment. A wide range
of customer-premises
terminates equipment,
which is connected to
the local
telecommunications
network. |
|
CSU |
Channel
Service Unit. |
|
DHCP |
(Dynamic
Host Configuration
Protocol) - A TCP/IP
protocol that allocates
IP addresses
automatically to any
DHCP client (any device
attached to your network
such as your PC) so that
addresses can be reused
when the client no
longer needs them. |
|
Digital
Loop Carrier
|
DLC.
Equipment used to
concentrate many local
loop pairs onto a few
high-speed digital pairs
or one fiber optic pair
for transport back to
the Central Office (CO). |
|
DSLAM |
(Digital
Subscriber Line Access
Multiplexer) – The
network device placed at
a telephone company CO,
that accepts all the DSL
lines from multiple
customer DSL connections
and puts the signals on
a high-speed backbone
line, with some
combination of ATM,
frame relay, or IP
networks. DSLAM enables
a phone company to offer
business or home users
the fastest phone line
technology (DSL) with
the fastest backbone
network technology
(ATM). |
|
Ethernet
|
A LAN
used to connect devices
within a single building
or campus at speeds up
to 10 Mbps. Ethernet is
defined at layer one
(physical) and layer two
(data link). Based on
Carrier Sense Multiple
Access/Collision
Detection (CSMA/CD),
Ethernet works by simply
checking the wire before
sending data. |
|
Firewall |
This is a
combination of software
and hardware that
filters or blocks
traffic from a public
network. A firewall
renders parts of the
private network
inaccessible and
invisible to the public
network. It prevents
unauthorized and/or
unrecognized access.
|
|
Hub |
A hub
connects devices
together. The key
characteristic of hubs
is whether or not they
are switched, and
whether they support
100mbps or not. For home
use, unless you are
doing some really
strange stuff, the
cheapest hub from a name
brand is adequate. For
DSL, one port will be
used by the DSL modem,
leaving the rest free
for your computers. |
|
IDSL |
IDSL is
DSL at 144 KBPS uses
ISDN transmission. IDSL
does not use any kind of
dial up nor involve
per-call fees. For those
that live too far. IDSL
is the only DSL option.
IDSL tends to be priced
at a rather higher rate
per bit of speed, than
any regular DSL. IDSL
can still be a very
satisfactory solution
for data transmission
compared to the
alternatives (modem). |
|
ILEC |
Incumbent
Local Exchange Carrier,
i.e., a regional Bell
operating companies,
i.e., the phone
companies. |
|
Inside wiring |
All phone
service wiring between
the Point of Demarcation
up to and including all
terminal devices in your
home. Telco refers to
this as the IW and
considers it subscriber
owned, meaning if there
is ever a problem that
degrades or eliminates
your phone service from
within the IW its up to
you to fix. |
|
IP
address |
Any
computing device that
uses the Internet must
be assigned an Internet
or IP address. All
workstations on a given
IP network use the same
IP network number, and
each workstation has a
unique IP host address
and an optional
subnetwork number. The
network and subnetwork
numbers together are
used for routing, while
the host number is used
to address an individual
host within the network
or subnetwork. |
|
Local loop |
The local
loop is the term for the
line between your house,
and the local switching
center. Since telephone
travels on twisted pair,
you can imagine one
phone company line to
your house as a big loop
of wire, hence the name. |
|
Maximum DSL speeds |
Maximum
DSL speed is a function
of distance, the gauge
(thinness) of the phone
wire used in your locale
and the DSL technology
employed. The fastest
DSL now commonly
available is ADSL, and
it offers maximum
download speeds of up to
7.1mbps and around 1.1m
upload. Most residential
ADSL is limited to
90-680k for download,
depending on the Telco.
SDSL currently has a max
of 1.5mbps, but that is
both up and down
(symmetric). |
|
NIC
(Network Interface Card) |
The
circuit board or other
form of computer
hardware which serves as
the interface between a
computer, or other form
of communicating. |
|
Ordering process |
Unlike a
dial-up Internet
account, the ordering
and installation of a
DSL line is lot more
complex. The ordering
process would typically
involve you locating an
ISP that can offer you
DSL, and then contacting
them by phone or email.
Some ISPs have online
query forms that allow
you to pre-qualify by
entering your zip code
and/or phone number,
which they check against
thier database to
ascertain if your zone
is lit up yet. When
looking for DSL service,
you should be aware of
how they intend to
deliver you service.
Whether it is dynamic
IP, or static IP. Also
what model of CPE
(customer premise
equipment) they propose. |
|
Point of Demarcation |
The point
near your premise where
the responsibility of
the phone company ends,
and the CLEC begins. |
|
POTS |
Plain Old
Telephone System! |
|
Router |
A router
is a network layer
device that uses one or
more algorithms to
determine the optimal
path along which data
should be forwarded.
Routers forward packets
from one network to
another based on network
layer information.
Routers are occasionally
called gateways, but
traditional gateways do
not translate data. |
|
Twisted-pair |
A common
form of copper cabling
used for telephony and
data communications. It
consists of two copper
lines twisted around
each other; the twisting
protects the
communications from
electromagnetic
frequency and radio
frequency interference. |
|
Static IP |
A fixed
IP makes it easier to
operate servers, as you
can happily assign a
domain name to it, and
hand out business cards
listing the name,
without finding it has
changed the next day. |
