[geeks] SunOS4/IPC: Change mac

Sandwich Maker adh at an.bradford.ma.us
Mon Dec 22 08:16:45 CST 2014


" From: Mouse <mouse at Rodents-Montreal.ORG>
" 
" > As I recall, 10 Mbs uses half the pairs in Cat5, 100 Mbs uses three
" > pairs, and Gigabit uses all four pairs... I'm sure this is documented
" > somewhere, but I'm also sure I've *mostly* got it right.
" 
" I _think_ 100Mb uses the same two pairs as 10Mb; it just uses them more
" demandingly (to deliver ten times the data rate).  Wikipedia's
" "Ethernet over twisted pair" page, misused punctuation and misplaced
" "only" aside, reinforces this impression, saying of 10/100/1000
" 
"    All these standards use 8P8C connectors,[note 1] and the cables from
"    Cat3 to Cat7 have four pairs of wires; though 10BASE-T and 100BASE-TX
"    only require two of the pairs.

roger that.  i recall there was also 100bt4, which used all pairs,
bidirectionally even, but if it did exist i guess it didn't catch on.
it was supposed to deliver 100Mb over cat3 iirc.

aha!  http://en.wikipedia.org/wiki/Fast_Ethernet#100BASE-T4
never common but the base for 1000bt.
________________________________________________________________________
Andrew Hay                                  the genius nature
internet rambler                            is to see what all have seen
adh at an.bradford.ma.us                       and think what none thought


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