After your students
research the problem presented in the scenario,
you have the option of conducting a videoconference between them
and a very special member of the Center for Educational Technologies®.
During the videoconference
your students can present their recommendations on which artifacts
work best for the museum display to none other than Meriwether
Lewis himself. Well, actually it's a Meriwether Lewis reenactor
who works at the center. He plays the role well and brings the
history of the expedition to life. The videoconference is worth
the effort for your students.
If you are interested
in conducting a videoconference, contact us at
firstname.lastname@example.org. You must schedule the event at least two weeks
In order to conduct
the videoconference, your classroom should have Internet access.
From your classroom you should also be able to transmit and receive
audio and video communication. This can be accomplished with an
H.323 IP videoconferencing unit (for example, Sony Contact or
Polycom Viewstation) or an integrated services digital network
(ISDN) videoconferencing Codec (for example, PictureTel, VTel
Galaxy, or ProShare) connected to the network.
An ISDN is a digital
phone service. It allows you to place calls that are digital end
to end as long as the person you are calling also has ISDN. Using
ISDN is a little more complicated than just hooking up to the
Internet. You must consider several issues:
Each ISDN line supports a data transmission rate of 128,000
bits per second (128 kbps).
Many ISDN-based videoconference systems have established
standards in their products. This allows products from different
manufacturers to call each other.
- H.320 is used by many manufacturers as a front-end protocol
to communicate with other systems. To use H.320, both ends
must support it.
- H.323 videoconferencing products are used for communicating
over the Internet. Sign language conversations can fluctuate
in quality on a call because the data rate is not dedicated
to the end-to-end smooth transmission of data, as is the
case with ISDN. However, many more deaf people have Internet
and high-speed lines than have ISDN service, so availability
is an important factor.
and H.261 are two widely used compression standards in videoconferencing
that exist within the main video call standards (H.320,
H.323, etc.). H.261 is older than H.263. Video performance
will increase using H.263 over the same transmission rates.
Avoid using H.261 unless the data transmission is very high
(384k or greater) and H.263 is not available. Be sure to
have H.263 support in H.320 standard. You may see H.263
for H.323 (Internet) only in some systems.
Progress A common frustration to the caller is not
knowing if the receiving station is busy or is not answering.
A display indicating the progress of the call (ringing, busy,
etc.) would be a helpful feature.
Video Leaving a small self-viewing video window in
a corner of the screen can affect receiving video performance
because of the CPUs being overwhelmed. A good example is the
PC-based VTel system. The receiving window will look a lot better
with higher frames per second when the self-viewing video window
is closed. Some systems do fine with the self-viewing window
Copyright © 2002-2003 by Wheeling Jesuit University/Center for Educational
Technologies®. All rights reserved.
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Classroom of the Future logo are registered trademarks of Wheeling Jesuit
The contents of this web site were developed under a grant from
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represent the policy of the Department of Education, and you should not assume
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project is being presented by the Center for Educational Technologies®
with financial assistance from The West Virginia Humanities Council, a state
affiliate of the National Endowment for the Humanities.