Last updated September 29, 2020 by Brian

You must use black outdoor cable outside. Indoor cable will last about 6 months outside due to UV damage. We mostly use Ubiquiti ToughCable Pro CAT5.

There is one commonly used standard for crimping ethernet: T-568B. (oO-gB-bG-brBR)

window/wall install source

A straight cable will work as long as both ends are the same configuration, but to stop confusion we only use the standard T-568B, which is the most common one in this country.

In 100base-T (100Mbps most old ethernet), orange is data transmit (pins 1 & 2) and green is receive (pins 3 & 6) pins 4,5,7,8 are not used for data.

In 1000Base-T (gigabit ethernet) all pins are used for data. If pins 4,5,7 & 8 are not connected the speed falls back to 100Mbps.

4,5,7,8 are used for 24 volt passive power over ethernet (POE). Pins 4 & 5 are positive and 7 & 8 are negative.

If you plug a live POE cable into an adapter or some device that does not expect POE it can break. This is often how ethernet adapters and cable testers break! A cheap USB 100Base-T ethernet adapter will survive as it doesn’t use the POE pins.

Ubiquiti POE is 24V DC, half the voltage of standard (802.3af/at) 48V DC POE. If you use standard POE you need to use a Ubiquiti 8023af-adapter

Ethernet cables need to be shorter than 100m (300’). Longer than that you will have data loss and the POE voltage will drop too low.