Interface Technologies
is a trusted name in corporate Toronto. With Interface DSL, you
can be sure you will receive the same high quality service and
personalized attention our clients have come to expect from us.
We have provided the following information to help answer any
questions that you may have about our DSL services.
still
have more questions?
Contact us
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What is DSL?
DSL (Digital Subscriber
Line) is a technology for bringing high-bandwidth information
to businesses over ordinary copper telephone lines. xDSL
refers to different variations of DSL, such as ADSL,
SDSL, and RADSL.
Assuming your business
is close enough to the central office of a telephone company that
offers DSL service, you may be able to receive data at
rates up to 6.1 megabits (millions of bits) per second (of a theoretical
8.448 megabits per second), supplying the necessary bandwidth
for numerous applications, including high-speed access to the
Internet, dedicated Internet connectivity, remote Local Area Network
(LAN) access, videoconferencing, and Virtual Private Networks
(VPN), continuous transmission of motion video, audio, and even
3D effects. More typically, individual connections will provide
from 1.544 Mbps to 512 Kbps downstream and about 128 Kbps upstream.
A DSL line can carry both data and voice signals with the data
part of the line continuously connected.
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How does DSL work?
Traditional phone
service (sometimes called "Plain Old Telephone Service"
or POTS) connects your business to a telephone company office
over copper wires that are wound around each other and called
"twisted pair". Traditional phone service was created
to let you exchange voice information with other phone users.
The type of signal used for this kind of transmission is called
an analog signal. An input device such as a phone set takes an
acoustic signal (which is a natural analog signal) and converts
it into an electrical equivalent in terms of volume (signal amplitude)
and pitch (frequency of wave change). Since the telephone company's
signaling is already set up for this analog wave transmission,
it's easier for it to use that as the way to get information back
and forth between your telephone and the telephone company. That's
why your computer has to have a modem --so that it can demodulate
the analog signal and turn its values into the string of 0 and
1 values called digital information.
Because analog transmission
only uses a small portion of the available amount of information
that could be transmitted over copper wires, the maximum amount
of data that you can receive using ordinary modems is about 56
Kbps (thousands of bits per second). ISDN, which one might think
of as a limited precursor to DSL, allows you to receive up to
128 Kbps. The ability of your computer to receive information
is constrained by the fact that the telephone company filters
information that arrives as digital data, puts it into analog
form for your telephone line, and requires your modem to change
it back into digital. In other words, the analog transmission
between your home or business and the phone company is a bandwidth
bottleneck.
Digital Subscriber
Line is a technology that assumes digital data does not require
change into analog form and back. Digital data is transmitted
to your computer directly as digital data and this allows the
phone company to use a much wider bandwidth for transmitting it
to you. Meanwhile, if you choose, the signal can be separated
so that some of the bandwidth is used to transmit an analog signal
so that you can use your telephone and computer on the same line
and at the same time.
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DSL
versus Cable
Over
the past few years, the Cable Modem has become the most popular
way to access the Internet in residential areas. When configured
properly and under optimal conditions, Cable has the capacity
to transmit data at speeds equal to DSL. However, Cable is not
available in most business areas, which means that it is not even
an option for most corporations. Cable was designed for residential
use, and in some cases may be a cost-effective solution for residential
high-bandwidth Internet access. Therefore, the question of Cable
vs. DSL is primarily an issue in the residential and telecommuter
markets. Residential Cable Modem service can be a good value for
high-speed access. Still, there are some significant limitations
for Cable Modem service even if your business is located in a
Cable-accessible area. Cable is a shared network, unlike DSL which
offers a dedicated line for each user. When too many users in
one neighborhood try to share the same cable, performance can
suffer dramatically and even grind to a halt as users compete
for the limited resources of one cable . For this reason, residential
Cable customers are not permitted to telecommute, host web sites,
use video teleconferencing and many other bandwidth intensive
applications. There are also certain security risks which can
make users more vulnerable to data interception, unauthorized
monitoring and hacking from other users along the same cable network.
All these conditions make it clear that as the decision-maker
in any business, DSL provides a more appropriate solution to the
dilemma of which type of Internet access to go with. DSL is specifically
designed to meet the varied needs of the business community, and
comes prepared to handle the complicated tasks the business world
asks of it.
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DSL
versus ISDN
ISDN
stands for Integrated Services Digital Network. There are several
reasons to choose DSL over ISDN. In terms of speed, ISDN is quite
limited: it is only available at 64 Kbps or 128 Kbps. To put this
in perspective, DSL scales from 128 Kbps to 2 Mbps! ISDN offers
dedicated, always-on access but comes with additional per-minute
charges. Expect to pay about $30/month to your phone company,
just for the line. Your ISP will also charge you anywhere from
$30-150/month. Then, add on 3 cents a minute for the first minute
and 2 cents for every minute you are connected thereafter. If
you are part of a business that requires Internet access 24x7,
be prepared for an ISDN line to cost hundreds of dollars per month
in usage fees. In fact, to be online with ISDN for as little as
one hour a day, you pay more than you would for 128 Kbps DSL connected
24 hours a day. Additionally, unlike DSL, ISDN requires the installation
of special digital circuits. DSL uses regular phone lines making
the installation process faster and far less complex.
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DSL versus T1
T1 is a technology
that bundles several phone lines together to provide downstream
access speeds of 1.54 Mbps. This is a very respectable speed,
and one of the benefits of T1 is that it allows a larger number
of users to be connected at one time than do the other types of
Internet access. However, most businesses find that they do just
fine without T1 once its pros and cons are put into perspective.
Since T1 requires the use of special lines, the installation process
is lengthy and complicated, as is the process of connecting private
networks from different regions. These are minor set-backs, however,
once a further variable is added into the equation. The decision
between DSL and T1 access becomes much more simple for most businesses
once cost is considered. Generally speaking, a business can pay
up to 4 times as much every month for a T1 line as it would for
DSL. In other words, for the cost of a single T1 1.54 Mbps connection,
you could install three 1.1 Mbps DSL connections. This is due
in large part to the fact that DSL uses ordinary, preinstalled
telephone lines. For this same reason, DSL also simplifies the
installation process and the interconnection of multiple networks.
When you look at these facts alone, it is easy to see why many
have termed DSL the "T1-killer". DSL continues to blow
away even its strongest competitors as more and more businesses
become aware of its simplicity, affordability and its potential.
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