I've got in-wall CAT5 wiring in my house. The wall sockets were done by an electrician and the requirement was straight-through T-568B, but I think he got it wrong. When I use a cheap cable tester, I see that one end obviously sends this sequence:
1-2-3-4-5-6-7-8 but the remote unit incorrectly reports with 3&6 swapped:
Given that not all wires are used, does this matter? I think it does; my understanding is that wires 1,2,3,6 are used but I'm no networking expert.
Lucky for me, the in-wall cabling ends in a patch panel so perhaps I should just open that up and swap all the 3&6 wires around -- but I don't want to do this unless I'm reasonably sure that'll help.
Also, would this wire problem cause the LAN to work normally at 100Mbit speed but not at gigabit speed, or is that unrelated? (I've asked about that already but just thought it might matter here.)