for full Gigabit hyperlinks, there isn’t a want for Auto-MDIX as a result of the PMA sublayer performs the identification of pairs so the hyperlinks work (autonegotiation and knowledge communication) with none kind of crossover (so a straight-through.
are the ideas of MDI interface versus MDI-X interface nonetheless related?
Sure: earlier than 1000BASE-T even begins the linking and pair identification course of, it must have been activated by Auto Negotiation which in flip requires matching MDI and MDI-X. Since 1000BASE-T makes AN obligatory (for grasp/slave choice), there is not any manner round it.
If you happen to discover the WP wording contradictory, the fault is all mine since I most certainly wrote that textual content. 😉
is Auto-MDIX related for full Gigabit hyperlinks?
Sure, even for 10/40GBASE-T hyperlinks.
Is it totally different that PMA identification of pairs mechanism or is it the identical factor?
Totally different since AN is a precondition for PMA.
if this PMA identification of pairs mechanism is so highly effective, can I wire the ends of an Ethernet cable in any random manner I need and nonetheless anticipate to have a totally functioning Gigabit hyperlink?
Sure, so long as AN nonetheless works. Though 1000BASE-T has its personal crossover cable kind (with all pairs crossed), it nonetheless works with basic crossover cables with simply pairs 1-2 and 3-6 crossed, and 3-4 & 7-8 straight (between two MDI or two MDI-X ports). Likewise ought to a cable with simply 3-4 and 7-8 crossed additionally work between MDI and MDI-X.
After all, Auto MDI-X is de facto required for contemporary networks. With out it you’d nonetheless want to pick out between straight and crossover cables, relying on linking gadget sorts. Nonetheless, Auto MDI-X just about comes ‘at no cost’ on 1000BASE-T interfaces (which require 4 transmitters and 4 receivers anyway) and with slightly low value on slower interfaces, so it is just about ubiquitous.