Network interface network crystal head RJ45, Poe interface definition line sequence

Crystal head connection

The picture above shows the home network crystal head 568-B The connection of . Crystal heads are common in our life and office networks , There is another way to connect 568-A We don't need to... In our life , So don't explain first .

This connection method can be seen everywhere in the weak current industry , For example, network surveillance cameras , LAN network cabling switches and servers , Connections between computers . For a 100m network, our crystal head only needs four pins to send and receive data, as shown in the following figure ：

pin assignment

POE Power supply pin

Now there are many POE Network equipment powered by network cable, such as the wiring of surveillance cameras, only need to pull a network cable to solve the power supply and data lines , Many routers AP Also have POE The power supply only needs to be connected with a network cable ,POE The pin of the crystal head of the power supply equipment is generally blue , White and blue , White brown , Brown , Two or four of these four , It depends on the specification of the equipment , There are some POE The device transmits in blue and brown .

Gigabit Network crystal head

For Gigabit bandwidth networks , The eight pins are all data transmission pins, and there are no vacant pins 1.2.3.6 For sending data ,4.5.7.8 Needle receiving data .