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Building the Ultimate, Low-Cost Internet Telephone/Videoconferencing Workstation
by Brian McConnell
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.
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