Comment by toast0
9 hours ago
You can run 100mbps with only two pair, if you have something on at least one end which you can tell to only negotiate to 100.
9 hours ago
You can run 100mbps with only two pair, if you have something on at least one end which you can tell to only negotiate to 100.
This is true. But you can also run gigabit ethernet over a single pair (1000BASE-T1) often called SPE. The transceivers are more expansive than normal four pair gigabit and the official cable requirement is Cat6A but even if the headroom is lower it will work on lesser Cat levels.
Single pair ethernet exists, but it's hard to find products with it. Would be nice if there were more media converters available.