On Sun, 03 Jun 2018 03:36:52 -0400, J. Clarke
wrote:

SNIPP
Then you don't get what noisy lines are all about, and what can create
them. Interference. Also just pulling too hard on Ethernet cabling can
stretch the wire messing things up.

So tells us of a documented case in which "pulling too hard on the
cable" or "interference" reduced the transfer rate for 1000BaseTX to 2
mb/sec. You're saying "can happen". So show us when it _did_ happen
or you're just spreading FUD.

If you pull too hard on a gigabit cable and damage the cable it will
NOT autonegotiate down.

I have seen it slow the network down SIGNIFICANTLY due to dropped
packets and retries - to well below a 2mb equivalent. Any one
conductor suffering damage in Gb ethernet WILL slow the network down.
Or kill it DEAD (at least the one segment)

A kinked Cat5E cable will fail the quality test for GB ethernet.
Running the cables parallel to a high current AC conductor will do the
same.



It won't slow down the bit-rate - but it will definitely cause
deterioration in the service via lost packets and retries, which
translates to a slower EFFECTIVE bit-rate.
SNIPPPPP

When talking 10BT /100BT, the troublesome auto-negotiation protocols
COULD downgrade a 100BT to 10BT, and often provided better throughput
on a reliable 10BT connection than on a flakey 100BT - but 10BT is "so
nineties"