Re: Chat works on D.C., but not when on reflectors....huh?

Dennis J. Streveler (
Thu, 27 Jun 1996 20:37:42 -0700

At 02:26 PM 6/27/96 -0500, tuffguy wrote:
>Hi there, I'm sure many of you have asked and/or answered this question,
>but I have had no problem with this dilema, so I'm sorry I haven't taken
>I got my Dad a quickcam for father's day, and he was very excited about
>getting up and running on CU... But now he has a problem with chat.
>When we DC to each other, all is fine...Vid, Audio and chat are great.
>But when he is on a reflector, although his vid and audio are OK, his
>chat isn't seen by anyone...Including me! What the heck is up with
>that? Any suggestions????
>His system(exactly the same as mine, and I have no probs!) :::
>Gateway p5-133, 16meg, 1.62gig, yadda yadda yadda... 28.8 modem etc...
>running the newest white pines enhanced. Local ISP.
>Any help very appreciated... I figure Mr Woodland will be responding
>soon, :) so thanx in advance, Bill, and any others, of course!!
> Mark Snodgrass


Recall that video, audio AND chat are all sent via Internet's UDP protocol,
which means the sender (i.e. the sending application) never receives
acknowledgement that packets are actually delivered. So,yes, it is possible
that chat packets, or packets containing audio, or packets containing video
can, and are, lost. You can monitor the "number of lost" packets statistic
and see if you are getting an inordinately large number of lost packets.

It is interesting, isn't it, that "chat" is the most vulnerable area. If
video packets are lost, you might lose a frame (or part of a frame update),
no big deal. If you lose audio, you normally know when you are expecting an
answer, and then you can say "are you still there?" or "did i miss your last
transmission?" or something and continue on. But with chat, you are not
always so sure that somebody is trying to send out a text message...

Hope this is helpful.


Dennis J. Streveler, Ph.D., | Internet:
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