@TracketPacer My memory is also that when Cisco did not win the autoneg standard. So when they moved to it some Cisco devices couldn’t interop with older Cisco devices. It was busted on 100M ports and didn’t get fully fixed until GigE. Then we had to retrain everyone to leave autoneg on.
@TracketPacer The first autoneg was vendor proprietary and 3Com (3c509 cards) did not interop with Cisco’s first catalysts. Worse, if one side was disabled (e.g. 100 full) the other side had to choose 100/half, always a mismatch. For a good 5ish year period hard coding both sides was SOP.