CU audio problems... connecting thru a reflector?

Dennis J. Streveler (
Mon, 03 Jun 1996 19:47:31 -0700


I don't think that a 1:1 videoconference can generally be improved by having
it pass through a reflector. It would seem that the 'law of conservation of
energy' would prevent this. :) That is, why have a packet go to a reflector,
be manipulated, and then sent on to its intended receiver, when that same
packet could be sent directly to its target?

I believe that the CU client has enough "smarts" to deal with mismatches of
transmission speeds (assuming that the transmission and reception rates are
set appropriately at both ends, a big assumption indeed!)

The real problem is with CU audio. While it uses the same Internet protocol
(UDP) as most other audio products, it is generally quite poor and
unreliable. While all products are subject to lost packets, CU seems to be
even more prone to lose packets than other (audio-only) products (such as
Internet Phone (for reasons that I do not fully understand since CU's
"codecs" are reputedly to be state-of-the-art also).

In fact there are times when I use ECU and IP together. One for video, and
the other for audio.

In summary, I don't believe that "connecting through a reflector will solve
most of your problems" unfortunately.


At 02:16 PM 6/3/96 -0500, you wrote:
>When you connect to a reflector, the reflector does more than just bounce
the signal to other multiple sites. A reflector also handles packets and
assembles them TOGETHER without losing them, or at least as many as are lost
with direct connections. If you both connect through a reflector, you will
solve most of your problems
>From: Luis de Miguel[]
>Sent: Monday, June 03, 1996 6:13 AM
>Subject: say what??
>While connected directly (he connects to my IP address) to a friend with
>a PC (Windows) we can see each other. He can hear me, I can't hear
>him. I can hear myself when I connect to "self" I can also hear the
>astronauts from the shuttle.
>When my friend connects to others (reflector), he is heard fine.
>My system: 520c PB, Mac OS 7.5, RAM: 24meg. Quick cam color.
>CU-SeeMe 83b3. T1 internet connection (University)
>Any suggestions?

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