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From: pat@hprnd.rose.hp.com (Pat Thaler)
Newsgroups: comp.dcom.lans
Subject: Re: RE: 10BASET CONCENTRATOR
Message-ID: <2230137@hprnd.rose.hp.com>
Date: 5 Feb 91 20:24:03 GMT
References: <1991Jan31.124812.6788@ibmpcug.co.uk>
Organization: HP Roseville Networks Division
Lines: 39

> 
>     
>     802.3 defines a repeater set which means just that, a set of 2 repeaters.
Actually, a repeater unit is the guts of the repeater, a repeater set is
a repeater plus its accompanying MAUs (transceivers).  In order to be able
to be precise in writing specifications for repeaters, it was necessary
to have terms which made it clear whether we were talking about the
repeater function or the repeater plus MAUs.

> 
>     Second;  What is a 10BaseT concentrator?  Simply stated, a multi-port
>     repeater that is constructed to drive twisted pair wire.  
 Or, you could say it was a repeater set with 10BASE-T MAUs internal to
 it.

>     Confusion should be
>     avoided by stating that 'one and only one port can be a receiving port
>     at any point in time'.  Or that' any port can be a receiving port as
>     long as no other port is receiving'.
Bob, you've gotten me confused now.  What confusion were you trying to
avoid?  There are times when two or more ports receive simultaneously;
that's called a collision.

>     fourth;  reference my original posting as to how many repeaters you can
>     have in an 802.3 network.  We still need to figure out how many standard
>     two port repeaters we can have in an 802.3 network.  We can have the
>     same number if they are multi-port.
> 
>     HINT 2;  If anyone, not on the committee, has a copy of the 10BaseT
>     draft standard you will find the limiting factor in the first paragraph.
Bob, are you implying that those on the committee are incapable of reading
the first paragraph or only that we don't get the prize for answering the
question?  Anyway, I spoiled the contest; I posted the answer in the earlier
string before I read this.

(BTW, I have a copy of the IEEE 802.3i, the _real_ 10BASE-T standard, 
published and everything.  Available now from IEEE.)

Pat Thaler