VoIP 101: Voice over IP for Beginners
For those who have never
heard about the potential of VoIP, be
prepared to radically change the way you
think about your current long-distance
calling plan. VoIP (Voice over Internet
Protocol) is very simply, a method for
taking ordinary analog audio signals and
turning them into digital signals that
can be sent over the Internet.
So what? Well, for those of you who are
already paying a monthly fee for an
Internet connection, this means that you
can use that same connection to place
free long distance phone calls. This
process works by using already available
VoIP software to make phone calls over
the Internet, essentially circumventing
phone companies and their service
charges.
Interestingly, VoIP is not an entirely
new thing. In fact, a number of
providing companies have been around for
some time. But it has only been with the
more recent explosion of high-speed
internet access usage, that VoIP has
gotten any attention. Now the major
telephone carriers are setting up their
own VoIP calling plans throughout the
US, another testament to the potential
of the technology.
How VoIP Is Used
While there are a number of ways that VoIP is
currently being used, most individual callers
fall into one of three categories: ATA, IP
Phones, and Computer-to-Computer.
ATA or Analog Telephone Adapter, is the most
common way of using VoIP. This adapter actually
allows you to hook up the phone that is already
in your house, to your computer, and then your
Internet connection. What the ATA does, is turn
the analog signals your phone sends out into
digital signals that can be sent over the
Internet. Setting up this system is quite
simple. It simply requires that you order an ATA
(its an adapter remember), plug the cable from
your phone which would normally go into the wall
socket into the ATA, and then the ATA gets
plugged into your computer, which is connected
to the internet. Some ATAs include software that
has to be installed on your computer before its
ready, but basically it's quite a simple
process. Then you are ready to make some calls.
The next type of VoIP usage utilizes IP Phones
instead of your home phone. The IP Phone looks
just like a normal phone, with all the same
buttons and cradle, the only difference is that
instead of having a normal wall jack connector,
it has an Ethernet connector. This means, that
instead of plugging in your IP phone to the wall
jack like you would with a regular analog phone,
it gets plugged directly into your router.
This option allows you to circumvent your
personal computer, and it also means that you
will not have to install any software, because
its all built in to the handset. In addition,
the fact that Wi-Fi IP phones will soon be
available, which will allow subscribing callers
to make VoIP calls from any Wi-Fi hot spot, make
this option an exciting possibility.
The simplest and cheapest way to use VoIP is
through computer-to-computer calls. These calls
are entirely free, meaning no calling plan
whatsoever. The only thing you need, is the
software which can be found for free on the
internet, a good internet connection, a
microphone, speakers, and a sound card. Except
for your monthly internet service fee, there is
literally no cost for making these calls, no
matter how many you make.
For large companies, VoIP also offers some very
unique possibilities. Some larger companies are
already utilizing the technology by conducting
all intra-office calls through a VoIP network.
Because the quality of sound is comparable to
and in some cases surpasses that of analog
service, some international companies are using
VoIP to route international calls through the
branch of their company nearest the call's
destination and then completing it on an analog
system. This allows them to pay local rates
internationally and still utilize the same
intra-office VoIP network that they would if
they were calling someone in the next cubicle
over.
Other Advantages of VoIP
While your current long-distance plan covers you
for only one location, say calls made from your
office, with VoIP, you can make a call anywhere
that you can get a broadband connection. That is
because all three methods above, unlike analog
calls, send the call information via the
Internet. This means you can make calls from
home, on vacation, on business trips, and almost
anywhere else. Anywhere you go, with VoIP you
can bring your home phone along with you. In the
same way, computer-to-computer connections mean
that as long as you have your laptop and a
connection, you're ready to go.
There are also some nifty benefits to having
your calls transmitted over the Internet. For
example, some VoIP service providers allow you
to check your voicemail via your e-mail, while
others allow you to attach voice messages to
your e-mails.
How VoIP Works
The current phone system relies on a reliable
but largely inefficient method for connecting
calls known as circuit switching. This
technique, which has been used for over 100
years, means that when a call is made between
two people a connection is maintained in both
directions between callers for the duration of
the call. This dual directional characteristic
gives the system the name circuit.
If, for example, you made a 30-minute call the
circuit would be continuously open, and thus
used, between the two phones. Up until about
1960, this meant that every call had to have an
actual dedicated wire connecting the two phones.
Thus a long distance call cost so much, because
you were paying for pieces of copper wire to be
connected all the way from your phone to the
destination phone, and for that connection to
remain constant throughout the call.
Today, however, your analog call is converted
after leaving your house to a digital signal,
where your call can be combined with many others
on a single fiber optic cable. While this system
is certainly an improvement over the past copper
wire system, it is still quite inefficient. This
inefficiency is due in part to the fact that the
telephone line can't distinguish between useful
talking and unneeded silences. For example, in a
typical conversation while one person is talking
the other person is listening.
Thus the current analog system uses roughly half
its space sending useless messages like this
silence. But there is also more information,
even down to pauses in speech, which under a
more efficient system can be effectively cut out
rather than wasting the circuit space. This idea
of only transmitting the noisy bits of a
telephone call and saving a great deal on
circuit space, is the basis of Packet-Switching,
the alternative method to circuit switching that
the VoIP phone system uses.
Packet-Switching is the same method that you use
when you view a website. For example, as you
read this website, your computer is not
maintaining a constant connection to the site,
but rather making connections to send and
receive information only on an as needed basis
(such as when you click on a link). Just as this
system allows the transfer of information over
the Internet to work so quickly, so also does it
work in the VoIP system. While circuit switching
maintains a constant and open connection, packet
switching opens connections just long enough to
send bits of data called packets from one
computer to another.
This allows the network to send your call (in
packets) along the least congested and cheapest
lines available, while also keeping your
computer or IP phone, free to send and receive
messages and calls with other computers. This
way of sending information, not to mention data
compression, makes the amount of information
which must be transmitted for every call at
least 3-4 times less for VoIP than the exact
same call in a conventional telephone system.
For this reason, VoIP is so much cheaper than
conventional calling plans.
The Future of VoIP
While most analysts believe it will be at least
a decade before companies and telephone
providers make the full switch to VoIP, the
potential for the technology's use today is
already quite astounding. A report by the
Forrester Research Group predicts that by the
end of 2006, nearly 5 million U.S. households
will be using VoIP phone service. With the
savings and flexibility that the technology
already offers, and new advances just ahead on
the horizon, we can expect those numbers will
only increase in the future.
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