Howdy!

"gb" wrote in message
...
"Ralph Wade Phillips" wrote in message
...


1000BaseT is 2 pair, and most Gigibit uses 2 pair.

If they didn't they couldn't do Power Over Ethernet (PoE)
injection
on the first pair, 4&5 B)

RwP

Power over Ethernet has TWO OPTONS
It can work on the 2 spare pairs with 10 and 100 Mb Ethernet (which uses 2
pairs and has 2 spare pairs)
OR on 2 data pairs when used with 1 Gb Ethernet (which uses ALL 4 pairs).
Read it yourself.

You are, of course, right.

That's what I get for "extending from previous learning experiences"
.... PoE has always been on pins 4 &5 in my past experience, and I've got at
least two customers with 100BaseTX stuff running over PoE connections
(webcams, both of them) to a gigabit switch (a Catalyst), with no seperate
injector.

Thanks for the education!

RwP