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Subject: Re: 'fxp' driver/hardware lossage (was Re: Alexander B. Povol's mail)
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Date: Sat, 27 Sep 1997 19:05:01 +0200
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> > Nope. A hub doesn't do anything with collisions - it just propagates
> > them bit by bit. The NICs sense the collision.
> 
> Better go think so more about that... it depends on the hub!  Some hubs
> that have partitioning ability will automagically partition out someone
> who starts to transmit if the hub is sending data out that port, this
> is called autopartitioning and is used to stop baligerant (sp) mau's
> or Jabberers(sp).

Sure - I agree it depends on the hub. But the basic task of the hub is to
propagate everything bit by bit - including collisions. And if you buy a
noname cheapie hub, it won't do much more than that.

> If you want something that really tries to ``prevent'' this you want
> a switch and not a hub, and you want full-duplex non-simplex NIC cards
> in every box connected to that switch, and no I'm not just talking
> about 100Base stuff here, it applies to both 10 and 100Base ethernet
> over TP.

Yup. But for normal, half-duplex Ethernet you *don't* want to prevent
collisions :-)

Steinar Haug, Nethelp consulting, sthaug@nethelp.no