Re: TESTING CUSM

Jason Williams (streak@ccwf.cc.utexas.edu)
Mon, 8 Sep 1997 14:40:29 -0500 (CDT)


On Mon, 8 Sep 1997, Andre Fleurant wrote:
> For the last couple of months I have been playing around with CU-SeeMe.
>
> I have 2 versions:
> Cornell's 0.92b2
> WhitePine demo 2.1.2
>
> I have been running them both on
> PC 486-66 32RAM 33,6modem
> Pentium 133mhz 32 RAM 28,8 modem
>
> On both systems I use Connectix's QuickCam (b/w)
>
> When getting on reflectors, there is not much that I see is being done
> other than video and chatboarding. I have never been able to hold a decent
> audio session with any of the two systems.
>
> I might (and must) be doing something wrong.

Holding a decent audio conversation on CU-SeeMe with only a modem is
tricky...Keep in mind that phone lines were never designed for data much
less video and audio streaming.
I've gotten audio working by:
1) setting my max send rate to 20kbps and pausing my video
2) setting my max receive rate to 20kbps and closing everyone else's
window
3) select 16kbps Delta-Mod with 100ms (or long delay on the Cornell
version)

It's all a matter of bandwidth...On the campus' T1/T3 I've listened to
live rock concerts with FM quality audio because there's enough bandwidth
there.

> I would expect CUSM to permit the use of videoconoferencing for the prupose
> of training with a maximum of 5 participants, making use of the White
> Board. I understand that this option does not exist in Cornell's.

On a modem, there's not enough bandwidth for more than 2-3 windows open at
the same time. Everyone slows down drastically beyond that from what I've
seen. The WhitePineBoard is only available in the White Pine versions.

> I would also be highly satisfied to be able to hold a point-to-point
> session making use of the whiteboard, the audio, and the video. Audio is
> more important to me than video, but video must remain active.

Both participants need the White Pine version (preferably the same WP
version as well as there are incompatibilites with different versions).
If both participants have a powerful enough system, you can set the audio
codecs down to 8kbps or so and have it work ok though a little muddled.
This uses less bandwidth and you might be able to send video at the same
time as well. As far as using the WhiteBoard..I've never had much luck
with it and White Pine emailed me saying the WhiteBoard is designed for
people with more bandwidth than a modem. Your mileage may vary :)

> Q1.
> Are the CUSM's developed enough to be used for good videoconferencing?

Depends on how you define "good"...CU-SeeMe will never deliver 30fps
640x480 pictures. A few years ago when I video conferenced with more
bandwidth, I rarely saw anyone send out more than 100-150kbps with
9-10fps. On a modem, "good" video conferencing is only a dream at this
point but nevertheless, it's definitely a fun program to play with.

> Q2.
> Up to what number of participant is the multicasting option of WP effective
> enough to not request the installation of a reflector?

I've never seen multicasting on CU-SeeMe work on a modem. I've only heard
about it working on LANs. If everyone is on a high speed LAN which
supports it, then it should work out ok. As far as the number of
participants, I'm not sure.

--
streak@ccwf.cc.utexas.edu    * Jason Williams -- Austin, Tx.  |     |
streak@mail.utexas.edu       * University of Texas at Austin  | ___ |
streak@cs.utexas.edu         * BS Computer Science             \_|_/
*************** http://ccwf.cc.utexas.edu/~streak/ **************|