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 Adaptor, is the most common way of using
VoIP. This adaptor 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 adaptor
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.