Http://blog.sina.com.cn/s/blog_4b650d650100g0ka.html
The principle of network cable circuit is relatively simple, that is, the Ethernet input and output interface into the circuit
The following is the RJ45 interface line definition:
PIN number function defines signal direction
rx+ (receive data positive) input
rx-(receive data negative) input
tx+ (send data positive) output
4;5;7;8 NC (empty)
6 tx-(send data negative) output
Make the network connector is to connect 1 and 3, 2 and 6 can be connected
1, prepare a common twisted pair, as long as two cores can be
2. Fold the twisted pair of wires
3, prepare a network cable of the Crystal Connector, the first two ends of the insertion 1, 3; Insert 2, 6 at both ends of the second root, as shown in the following figure
1------------|
2-----| |
3-----|------|
4 |
5 |
6-----|
7
8
4. Clamp with clamp Line clamp,
5, will do a good crystal network Loop Connector access network card can be.
In order to test the network port of each computer in the production of the computer is working properly. We thought of a loopback test method. On the Internet, the introduction of the production of loopback Crystal Head is a lot of methods, but the detailed introduction of the test method of the article is very few. After reviewing the materials and experiments, summed up the introduction of everyone.
The first is to make a loopback crystal head. The purpose is to make the data sent by the PC through the network card be received by itself, that is, loopback. Then make the crystal head to see if your network card is a gigabit network card or thousands of gigabit network cards. If it is a gigabit network card, connect the 1,3 feet of the network cable and connect the 2,6 feet. That is, the hundred-gigabit card only uses 4 lines of the network cable. For the Gigabit network card, but also to the 4,8 feet, 5,7 feet connected. I downloaded a diagram to describe the connection method.
Once connected, the loopback crystal Head is ready. Then there's the experiment.
The first thing to do is to configure the PC as a non-automatic way to get an address. That is, configure your network card, set an assumed address, such as 10.10.1.2, in a reasonable configuration subnet mask and gateway, such as 255.255.0.0,10.10.1.254. So your network card is configured. To configure a pinned site to insert a loopback crystal Head, the system finds that a network cable is plugged in faster.
Next, you can experiment, in the non-plug loopback crystal Head, ping 10.10.1.2, the result of the operation is the network does not pass. Insert the crystal Head, you will find the network card light on, that is to say that your crystal head connection is correct. To run Ping 10.10.1.2 again, if the ping is on, then your network card is working properly. Otherwise the NIC has a problem and needs to be repaired.
In addition, if you want to know the error rate of your network card, you can use Ping's-N, option to contract and query the speed of the packet collection. Well, there's a trick that you find that the interval between each packet of ping is about 1s, and if you're going to send 100 packets, you'll need 100 seconds. This will be very slow. I guess this is the ping command. In order to display the process to the user, the program delays between each package. If you want to get a quick contract, You can use ping to send one package at a time, for example: Ping-n 1 10.10.1.2, so that you can use the Loop 100 times in your program, which will greatly increase the speed of the contract.