Hello Jens,
I do not know how to answer your "7 LAN connection."
The standard (normal) or crossed cables were once required before current Ethernet chips could auto-sense the TX/RX pairs.? That was when the router to switches needed a different connection than the switch or router to a device.
As to length, standard Ethernet cables can be up to 100 meters in length before an amplifier or switch is needed to boost the signal.? Any standard cable should work.? If there are high RF fields, then a shielded cable would be better to reduce interference with the connection.
73
Evan
AC9TU
