
A Guide for Online Information
About:
Internet Phones
by Rick
Prescott
Part: 1 2
In the past, Internet
phones have not been much of anything to talk about. Several factors
contributed to their downfall: sound quality was poor, and both parties
had to be online and using the same software. On top of that, you couldn't
call someone who used an ordinary phone.
Now there's a new
generation of services for calling over the Internet. You can even call
someone that does not own a PC. The sound quality has improved. Sure,
sometimes you sound like you're calling on a chintzy cell phone from
a closet in Lithuania, with cotton in your mouth. But when Internet
phones work perfectly, which happens about a third of the time, calls
on at least two 'Net phone services (namely, Deltathree and I-Link's
TalkFree) sound almost as good as if you were on a landline. And, you'll
definitely save money. Using Internet phones to call numbers within
the United States, and to call many overseas countries, can't get any
cheaper than free.
Nonetheless, traditional
phone companies probably will not start losing customers for quite some
time. The developing technology is still too unreliable. But with a
little planning, the right equipment, and a few tricks, 'Net phones
are reasonably serviceable for calling friends and family around the
U.S. and in other parts of the world. (more)
How
It Works
Aside from the obvious fact that you're talking into your PC instead
of a handset, web phones differ from real phones in at least two important
ways. First, rather than using the telecommunications network provided
by your long-distance phone company, web phones use the network (or
the combination of networks) that makes up your Internet connection.
Part of that network is probably a phone company's network, but part
might include your internal corporate network as well.
Second, you're sending
the digital data representing your voice over a network that doesn't
guarantee specific levels of service. That is, while regular phones
let you and the person you call speak as if you were in the same room,
the Internet can't guarantee that kind of responsive, high-quality service.
(more)
Pull back the wires
and the technology behind Internet phone calls is easy to understand.
You speak into your computer's microphone or headset; a program then
digitizes your voice, divides the words into data packets, and sends
them hurtling through the Internet toward the person you're calling.
When the transmission arrives at the other end, a matching program or
a hardware device reassembles the packets, and your friend hears your
disembodied voice. If all the packets make it through okay, you sound
great; if not, your buddy will hear echoes, distortion, or worse audio
glitches. (more)
Types
of Phones
Internet phone services let you communicate in a number of ways. You
can make an Internet call from one PC to another by dialing the Internet
Protocol address of your friend's computer. The software lets you type
in the digits of the IP address, and then you start talking. Several
services let you place a call from your computer to your friend's regular
phone. The PC-to-phone feature is astonishing. The other person needn't
be near, or even own, a computer.
About half the products
can be used directly from the companies' web sites or upon downloading
a small program. Some of the software, such as PhoneFree, MediaRing
Talk, and Deltathree, support better-quality connections than their
respective browser-based programs.
When signing up,
you will have to answer the questions typical of free services. After
you've registered, a telephone dialing pad pops up on your screen. Punch
in a number (or grab it from the service's address book), click the
button to dial the number, wait a second or two, and you're connected.
All services (with the exception of TalkFree) let you talk with no time
limit. (more)
What You'll Need
To get started using an Internet phone service, all you need is a sound
card with a microphone and speakers, a 56-kbps modem, an Internet connection
(AOL is okay), and a browser. To increase your chances of making the
service work right, though, you need to do a few things.
First, make sure
your sound card is full-duplex, and upgrade if necessary. Most old sound
cards are half-duplexyou'll know you have an older card if only
one person can talk at a time, as with a two-way radio. If you're running
at half-duplex, you might be able to fix the problem with a new driver.
Check your sound card maker's web site for an update.
Next, you should
consider buying a sturdy headset. This device will help block external
noise, making it easier to hear the caller. And in most cases, a headset
is superior in quality to the stick-like microphone that sometimes accompanies
sound cards. Even poor connections sound better over a good headset.
If you have a dial-up
connection, you must use a 56-kbps modem. Anything slower and you'll
experience dreadful voice qualitystatic, dropped words, and echoes.
If you want your Internet phone to work like a regular phone and you
plan to use it on a regular basis, get a high-speed DSL or cable modem
connection. Voice quality was substantially better (but still imperfect)
in all my tests using cable or DSL. (more)
Net Phone Tips
You may not be able to make Internet calls from work if your company's
IS department uses a firewall. Check to see if a specific port on your
PC can be opened for outgoing calls. Note: Any personal firewall you
might use, such as Zone Labs' free ZoneAlarm, can accommodate Internet
calls.
If you're using
a 56-kbps connection and the voice quality is poor, hang up and try
again. Still awful? Switch to another of your ISP's dial-in numbers.
If you're having
trouble with sound quality, experiment with the product's microphone
and speaker settings while you're connected. For instance, Deltathree
worked best with the mike set to low and the speaker to high. (more)
PC
World Evaluated Services
Deltathree
Free PC-to-phone calls in U.S.
Free PC-to-PC calls
Voice mail/personal address book
PRO: Consistently good voice quality, clean interface, handy address
book, free calls to directory assistance.
CON: Limited speed dial, flashing ad.

Dialpad
Free PC-to-phone calls in U.S.
Free PC-to-PC calls
Voice mail/personal address book
PRO: Simple, easy-to-use interface; voice quality often good.
CON: Company ad takes up lots of space; two separate windows--one for
dialing, one for address book.

Firetalk
Free PC-to-PC calls
Voice mail/personal address book
PRO: Instant messaging; easy to use once you learn to navigate.
CON: Small Web-based window crammed with information; PC-to-PC calls
only.
HotTelephone.com
Free PC-to-phone calls in U.S.
Personal address book
PRO: Free overseas calls.
CON: No PC-to-PC calls; separate windows for dialing and address book;
irritating flashing ads.

MediaRing
Free PC-to-phone calls in U.S.
Free PC-to-PC calls
Voice mail/personal address book
PRO: Cool-looking interface; free calls to China; lets you send e-mail
messages with streaming technology.
CON: Flashing ad; separate field for country code.

Net2Phone
Free PC-to-phone calls in U.S.
Free PC-to-PC calls
Voice mail/personal address book
PRO: Voice mail and faxing; free headset after you purchase call time.
CON: Ad hogs screen; field where you enter number is somewhat awkward,
can't use number keypad.
NEXT
I am always
looking for more material about interesting subjects. If you would
like to share more information about robotics or would like to see
a Resource Page on a particular topic, contact me,
Rick
Prescott.
Circuit Cellar provides
up to date information for engineers, www.circuitcellar.com for more
information and additional articles.
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