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- Newsgroups: comp.dcom.cell-relay
- Path: sparky!uunet!sun-barr!ames!sgi!rhyolite!vjs
- From: vjs@rhyolite.wpd.sgi.com (Vernon Schryver)
- Subject: Re: Curious attitude ...
- Message-ID: <nu696eo@rhyolite.wpd.sgi.com>
- Organization: Silicon Graphics, Inc. Mountain View, CA
- References: <12387@pinard> <22041@venera.isi.edu> <1992Jul29.164110.1@research.ptt.nl>
- Date: Thu, 30 Jul 1992 04:10:51 GMT
- Lines: 41
-
- In article <1992Jul29.164110.1@research.ptt.nl>, walvdrk@research.ptt.nl (Kees van der Wal +31 70 332 6295) writes:
- > In article <22062@venera.isi.edu>, finn@isi.edu (Greg Finn) writes:
- >...
- > > No. Multicast is NOT broadcasting. A routing tree is
- > > constructed so that the traffic flows according to what is ideally a
- > > minimum-cost spanning tree. Hardly broadcast I think.
- >
- > I agree. The essence is that there's hardly any real time contraints when
- > doing none-interactive multicast.
-
-
- Wasn't the IETF multicast "interactive"?
-
- If you don't have some real time constraints, pictures get objectionably
- jerky and voice is hard to understand.
-
- Do you guys not like "etherphone", from many, many years ago? You can
- make a similar thing that works pretty well on modern workstations that
- support sound.
-
- 50 milliseconds is not at all hard to hit on typical ether-internets,
- with workstations acting as routers. (I know a little of such an
- internet with a hundred or so ethernets, some FDDI and TR and a few
- thousand workstations, and a little more about the hardware and
- software of those workstations.) Sometimes round trips get worse than
- 50 msec, but then I've noticed my telephone tends to not work very well
- shortly before the building is rattled by thunder.
-
- Do you guys think that all of the "multi-media" people are without a
- clue or a hope? (I think many lack one or the other, but few lack
- both.)
-
-
- I'm trying to politely suggest that you telephony guys should get out
- more. See other parts of the world. Good data networking people
- generally know they don't know about telephony, but it is strange the
- obverse does not seem to apply. (I won't claim in public to be good,
- but I will claim to not know too much about telephones.)
-
-
- Vernon Schryver, vjs@sgi.com
-