ADSL
(Asymmetric Digital Subscriber
Line) - A term for one-way
high speed transmission of
signals over plain single
twisted-pair wiring already run
to residences. ADSL is
provisioned with greater
downstream than upstream rates
(hence asymmetric). These rates
are dependent on the distance of
the user to the Central Office
and can vary from as high as 6
Mbps to as low as 128 Kbps.
Adapter Card -– An
electronics board installed in a
PC, which provides a network
interface to and from that
computer. Also called a network
interface card (NIC).
Bandwidth - The amount of
information or data that can be
sent over the Internet during a
given period of time. Bandwidth
is usually stated in bits per
second (bps), kilobits per
second (Kbps) or megabits per
second (Mbps).
Bridge - A data
communications device that
connects two or more networks
and forwards packets between
them and function as routers.
Bridges read and filter packets
and frames. Bridges do not
require IP addresses and will
pass broadcast traffic.
Broadband - A
transmission medium or channel
that has a wider bandwidth than
one voice channel (with a
carrier wave of a certain
modulated frequency). It allows
multiple services like voice,
data, video, etc. to transit
over the network.
CO (Central Office) - A
circuit switch that terminates
all the local access lines in a
particular geographic serving
area; a physical building where
the local telephone company’s
switching equipment is found.
DSL lines running from a
subscriber’s home connect at
their serving Central Office.
CPE (Customer Premise
Equipment) – Communications
equipment that resides on the
customer’s premises. The CPE for
DSL services is a DSL router or
bridge.
Dedicated Line - – A
transmission circuit that is
reserved by the provider for the
full-time use of the subsriber.
Downstream/Upstream -
Downstream refers to data
flowing from the source such as
an Internet service provider
(ISP) to the end user. Upstream
refers to data flowing from the
end user back to the ISP.
Firewall - A firewall is
a set of related programs,
located at a network gateway
server, that protects the
resources of a private network
from users from other networks.
(The term also implies the
security policy that is used
with the programs.) An
enterprise with an intranet that
allows its workers access to the
wider Internet installs a
firewall to prevent outsiders
from accessing its own private
data resources and for
controlling what outside
resources its own users have
access to.
Kbps (Kilobits per second)
- – A measure of bandwidth
capacity or transmission speed.
The acronym stands for a
thousand bits per second.
Mbps (Million bits per
second) -– A measure of
bandwidth capacity or
transmission speed.
NAT - Network Address
Translation - Provides a
pseudo-dynamic connection with
the internet in a private IP
space. This is ideal for most
instances where a static IP is
not required. If you want to
read email, news, and browse the
web at the highest possible
speeds and the lowest cost, then
this is the choice for you.
NIC (Network Interface Card)
- The circuit board or other
form of computer hardware that
serves as the interface between
a computer and the
communications network.
Router - The device that
connects multiple computer
networks by reading the address
information on all data packets.
The packet information is read,
and the packets are then
forwarded to the appropriate end
station. Routers provide more
functionality than bridges,
which simply connect dissimilar
networks.
SDSL (Symmetric Digital
Subscriber Line) -– Also
called single line service, SDSL
provides the same amount of
bandwidth in both directions.
Upstream - Refers to data
flowing from the end user back
to the Internet service
provider. |
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