Re: CU-SeeMe - Does Audio work on a Modem?

Gary Dietz (
Tue, 06 Jan 1998 15:32:59 -0500

>I've had some interesting experiences with audio that I don't quite
>understand. Using the 2.1.2 version (the only WP version I can get audio
>to work with), the quality of a single audio codec depended on what
>sending codec I had it set to. The sound coming from other participants
>when I had it set to Digitalk was drastically different than when I had it
>set to Delta-Mod..even when they were sending the same codec all the time.

Perhaps because your CPU usage differed depending on what you were
encoding. Thus the CPU available for decode differed?

>> c. Don't expect to open 12 video windows, a whiteboard, and get audio on a
>> 33.6 connection. It ain't gonna happen! Or, if it does, it will be very
>> slow.
>I wouldn't expect to open the whiteboard at all on a modem :)

I've personally done this with 3.1 on a 33.6 to 33.6 connection on a public

>> f. On a "public" server, you never know who is sending what or how they are
>> sending it. If you run (or rent time) on a private server, you'll usually
>> have better group conferencing results. And, with security and parental
>> control needs, it is much better to purhcase your own server, or go to
>> Powerscourt to rent time on a server.
>Nice advertising :)
>I don't quite see how conferencing on a private server is any different
>than conferencing on a fairly unused public server with respect to the
>quality of transmission and reception of audio.

All of these are possibilities:

1. The "private" server is a faster machine with more memory

2. The "private" server has scheduling, and thus the usage levels are under
the control of the owner

3. The private server has a better, more reliable connection to the Internet.

4. In a private environment, as an Admin I may know who has what equipment;
Thus I know that someone using a 486 PC won't be trying to run CU 3.1 with
G.723 audio and then saying it doesn't work ;-)

5. In a private environment, I'm more able to take time with the clients to
make sure that their PC/MACs are set up correctly and that they have
effective quality mikes.

6. The private server is MeetingPoint and not the Cornell reflector. (Yes,
another ad...;-)

I think 1/2 of why Jason always is so contrary to my statements is this:

His idea of a "reflector" is a free public service to be offered to be
connected to by anyone anytime.

My idea of a conference server is also that, but add the idea of a
privately run server used for other purposes (like distance learning or
business conferencing). In my experiences, when the environment is
controlled, the results are better (that's true for all software... not
just CU/MPCS).


It's just as easy for
>someone to have screwed up rates on a private server as it is for a public
>server (After running both public and private reflectors..I can vouch for
>Of course...with programs like Refmarshal out there, more and more
>reflectors (both White Pine and Cornell/Enhanced Reflectors) can be
>controlled with a nicely designed interface. The issue of monitoring and
>controlling will eventually be a thing of the past with more reflector
>operators taking advantage of the tools out there.
>> i. Finally, CU-SeeMe 3.1 has improved audio subsystems, and you'll get even
>> better results even if you just use the Voxware codec.
>improved? I'll let you know if and when I can get it to work :)
>Also keep in mind, not EVERYONE uses CU sending G.723 audio to a
>non-3.1 user has little effect. It's why a lot of people are still
>sending in B&W from what I've seen...backwards compatibility.
> * Jason Williams -- Austin, Tx. | |
> * University of Texas at Austin | ___ |
> * BS Computer Science \_|_/
>*************** **************|

  Gary Dietz, Product Manager, Vertical Solutions 
  White Pine Software Incorporated
  542 Amherst Street, Nashua, NH 03063
  603-886-9050 x356    
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