Building the Ultimate, Low-Cost Internet Telephone/ Videoconferencing
Workstation
You can turn your desktop computer into a powerful communication
platform for telephony, videoconferencing, and whiteboarding (2 or
more people working on the same document at the same time). However,
until recently, installing the hardware and software needed to make
this work was difficult. Fortunately, this has all changed with the
introduction of several new products and technologies which provide
high-quality video and audio at a low price.
This short tutorial explains how to turn an ordinary desktop
computer into a multimedia communications platform which you can use
to communicate internally, and with people outside your company (via
the internet). The cost to build this system, excluding the
computer, is less than $300. If you use the system to communicate
with people in other cities, the system will pay for itself in the
form of reduced telephone tolls. Apart from the cost savings, you'll
be able to communicate in ways you were not able to before.
Step one - upgrading your PC
While you can do this on Windows 95, it will be much easier to
install and configure the audio and videoconferencing hardware on
Windows 98. Windows 98 adds support for a new technology called
Universal Serial Bus (USB).
This is the single most important improvement in Windows 98, and
it's importance cannot be overstated. USB is an expansion bus which
enables you to connect many different kinds of peripherals
(printers, video cameras, audio devices, disk drives, etc.) to your
computer. Unlike older systems, USB is "hot swappable." This means
you can connect and disconnect peripherals while your computer is
running. You can also connect many more peripherals to a single USB
port than conventional serial ports.
First, check to see if your computer has a USB connector. If it
does, then you should not have to upgrade your PC to support USB.
You may need to go into your computer's setup (or BIOS) screen to
activate USB support. (When you boot your computer, you will usually
see a message like "Press F1 for setup" before it loads Windows.
This leads to the BIOS/setup menu). Do not make changes to your BIOS
settings unless Windows 98 is unable to detect devices connected to
your USB port. This should work automatically.
Second, you will probably want to invest in a device called
a USB hub. A USB hub allows you to daisy chain many devices off of
one USB port. Most PCs have 1 or 2 USB ports, not enough if you plan
to connect many peripherals. A USB hub will also help by putting the
cabling/plugs in a more accessible location. Most USB ports are
located on the back of the computer (difficult to get to). You can
put the USB hub on your desktop so you have easy access to USB
ports.
Belkin makes a reasonably priced 7-port hub (supports up to 7
devices).
If your PC does not support USB, you can add USB support with an
expansion card. You need to have at least one PCI expansion slot in
your PC to do this. If your PC is several years old, you might want
to think about upgrading to a new machine so you don't need to
bother with this. If the machine is less than 2 years old, this
should work fine. If you don't have any free expansion slots, you
can also find converters which turn a parallel (printer) port into a
USB port (although you should expect lousy performance). The good
news is that most PCs sold in the past year or so have USB
connectors built in.
Next, you need to make sure your PC is fast enough for the job.
Internet telephony, and particularly videoconferencing, require a
lot of computing horsepower. This is because the audio and video
signals are compressed to reduce the amount of information which
needs to be transmitted between endpoints. This process is very
computationally intensive, so a fast PC with lots of memory (64 MB
or more) will make a big difference in performance. Generally
speaking, if your PC has a 200 MHz processor or faster, and 48 MB of
memory or more, you should be in good shape.
Step two - upgrading your PC's audio system for live
conferencing
Most computers have high-quality sound systems built in.
Unfortunately, the sound system in most PCs is designed for playing
and recording audio files, not for real-time audio services like
telephony. Because of this, you get less than optimal performance
when you use your PC's built-in sound card to place internet phone
calls.
Quicknet Technologies makes an excellent audio card designed
specifically for network conferencing called the Internet PhoneJACK.
You can use it with a headset, or you can connect an ordinary
telephone to the card (the phone is tricked into thinking it is
connected to an ordinary phone line).
The Internet PhoneJACK supports what is called "full-duplex"
operation. This means both parties in a conversation can be talking
at the same time. Most PC sound cards only support "half duplex"
which means that only one party can be talking at a time, the result
is an awkward "walkie-talkie" effect similar to that encountered
when using a cheap speakerphone. The Quicknet card includes several
other features designed to improve performance. One is echo
cancelation. This means the card automatically eliminates echo from
your conversation. It takes a while to explain why network phone
calls are prone to problems with echo, but the Quicknet card takes
care of it. Lastly, the Quicknet card has its own microprocessor
designed to compress the audio signal. This dramatically reduces
latency, or delay, which is common in network phone calls.
Installing the Quicknet card is easy, and requires a single ISA
expansion slot. The card is plug-and-play compatible, so it will be
automatically recognized when it is installed in a Windows 95 or
Windows 98 machine. It can also be installed in a Windows NT
machine, but this is a bit trickier. The
Quicknet Internet
PhoneJACK sells for about $160.
There are other full-duplex audio cards, but to date the Quicknet
card is the best product we have seen for internet teleconferencing.
Step three - adding video to your PC
Next, you need to add full motion video capability to your PC. This
used to be a difficult and expensive process, requiring the
installation of video capture cards, balky software, and so forth.
The good news is that with the arrival of USB, you can now buy
cameras which simply snap into a USB port. We looked at several
low-cost USB cameras which were designed with videoconferencing in
mind, including the
Logitech QuickCam and the
Kodak Digital Science DVC323.
The Kodak camera was our hands-down favorite. The DVC323 is
a plug-and-play color video camera which produces sharp (up to 640
by 480 resolution) images at speeds of up to 30 frames per second
(same as broadcast TV). The camera was very easy to install and
mount, and produces good quality images, especially considering that
the camera sells for less than $150. The camera ships with software
that enables you to tweak camera settings to deal with different
lighting conditions, optimal picture quality, as well as photo
software which enables you to use the camera to shoot still images.
The DVC323 is compatible with Microsoft NetMeeting, one of the
most popular videoconferencing programs on the market, and produces
good quality images for video calls.
We also looked at the Logitech QuickCam. This is a good
product, but in our experience the picture quality was not as good.
The colors tended to be washed out, and the pictures were not as
detailed. Also, the camera's mount was poorly designed, so the
camera was easily knocked off its mount whereas the Kodak camera was
much harder to knock off balance.
Since both cameras sell for approximately the same price, we're
currently recommending the Kodak DVC323 camera as the best choice.
Step four - installing Microsoft NetMeeting
Microsoft NetMeeting, now bundled with Internet Explorer version 5.x
and later, is a free audio/videoconferencing program which allows
you to place phone and video calls over your PC network or over the
internet. NetMeeting complies with the H.323 standard, an important
industry standard for network phone and video calls. This means you
can use NetMeeting to make and receive voice and video calls from
other H.323 compatible programs and devices (such as
videoconferencing terminals).
Microsoft NetMeeting provides the following services:
- Internet telephony: make and receive voice calls over the
internet (or your company network)
- Internet videoconferencing: make and receive video calls over
the internet (or your company network)
- Application sharing: work collaboratively on a document or
presentation
- Whiteboarding: create a virtual drawing board which you can
scribble on
- Text chat: exchange text messages with other parties
Microsoft NetMeeting can be installed with Internet Explorer. To
download it, visit the
Microsoft Internet
Explorer web site or the
Microsoft NetMeeting
web site.
|