ADSL twisted pair issues, twisted pair network cable usage issues

The difference is a bit big, the principle of ADSL is to use ADSL cat to separate the signal of the low frequency band and the signal of the high band, and the cat only reads the signal of the high frequency band, so the **line is an ordinary**line, and the difference between the network cable is big.

ADSL is an Internet broadband technology, the cat is: modem, modem, this is the device that converts the analog signal in the ** line into a digital signal. That line is the same. In the past, the modem dialed with ** line was very loud, like a cat meowing, so it was referred to as a cat.

**The line can be connected to the Internet, but after the signal is modulated and demodulated, it can actually be used as a **line, but the twisted pair is usually 4 pairs of lines (super five categories: 2 receiving and 2 sending, and the other 2 pairs of lines are spare), **only using 1 pair of wires (1 receiving and 1 sending).

The reasons are: because the twisted pair is a baseband transmission, it is a digital signal, which is affected by the transmission medium and is usually valid within 100 meters, and the signal will lose frames beyond this distance; The ** line is a frequency band transmission, which is an audio signal and can transmit long distances.

Because the computer can not identify the frequency band signal, so we usually use the first line to surf the Internet, in fact, the information is sent from the server on the Internet, after transit, modulated as the frequency band signal is transmitted by the first line, and then demodulated by the modem for the baseband signal, transferred to the computer to receive and process.

By the way, the twisted pair is actually the same as the ** wire from the transmission medium, which is a copper core wire, but the reason why it is called a twisted pair is because it has 4 pairs of wires, and each pair of wires is twisted together. Because copper medium is a transmission medium with relatively large interference by itself, the use of twisted pair is to avoid the near-end crosstalk value that is easy to occur in the process of signal transmission, which directly affects the signal quality.

Their interfaces are different! In other words, different standards are used! **The line is RJ32 and the network card is RJ45They are completely different!

The twisted pair is used because the capacitance formed by the wire pair forms a series inductor in series, and the inductor acts on the opposite of the capacitor to make the signal phase ahead. The function of twisted pair wires is that the inductance and capacitance cancel each other out, so that in ideal cases, the signal can be less attenuated. To put it simply, the twisted pair can resist some external electromagnetic interference, and more importantly, reduce the external interference of its own signal, so as to maintain the stability of network transmission.

In order to avoid crosstalk between pairs, the twisted density (pitch) of adjacent layers and adjacent pairs is different in a network cable class.

Twisted pair (TP) is the most commonly used transmission medium in integrated wiring engineering, which is composed of two copper wires with an insulating protective layer. Two insulated copper wires are twisted together according to a certain density, and the radio waves radiated by each wire in the transmission will be canceled by the radio waves emitted by the other wire, effectively reducing the degree of signal interference.

Twisted pair wire is generally made of two 22 26 gauge insulated copper wires wound with each other, from which the name "twisted pair" comes from. In practice, twisted pair wires are made up of multiple pairs of twisted pairs wrapped together in an insulated cable sleeve. If one or more pairs of twisted pair wires are placed in an insulating sleeve, it becomes a twisted pair cable, but in daily life, "twisted pair cable" is generally called "twisted pair".

The network cable generally only uses these 4 lines, and the corresponding colors are white orange, orange, white green, and green.

Direct connection means that both ends are the same. The cross-connect method is one of the headers and inversions.

In actual use, both the route and the switch can automatically identify the signal port, whether it is a multi-level route or a multi-level switch.

Cat-router-switch-computer, all of which can be directly connected.

Route-switch-computer, you can also use the crossover method.

Computer A - Computer B - Computer C, only the cross-connect method can be used.

When the distance between the route or switch and the computer is long, for example, greater than or equal to 100 meters, and the direct connection signal is not very good, the crossover connection method can be used, and the signal is slightly better than the direct connection.

Here it is recommended that you use direct connection, which is simple and easy to operate, and it is easy to deal with problems at the end of the line.

Cross connection is used for the same device, and direct connection is used for different devices. However, many devices now have adaptive.

Router-computer-crossover.

Router-Switch-Direct Connection.

Switch-PC-Direct connection.

Today's devices generally support the automatic port flip function. Both types of network cables can be used.

I don't understand your question. Do you mean cross-play and straight-to-straight play? The common way to play with a network cable cross is white orange, orange, white-green, blue, white-blue, green, white-brown, and brown at both ends.

The direct connection is one white orange, orange, white-green, blue, white-blue, green, white-brown, brown and the other end is white-green, green, white-orange, blue, white-blue, orange, white-brown, brown cross is the computer with the switch, and the direct connection is the computer with the computer.

Ask me again if you have any questions.

1) Generally, the commonly used network cable is also called twisted pair, the plug is called RJ45 port, which can be connected to a computer or broadband, a total of eight wires. But it is 4 of the threads that are actually used.

2) ** line in principle can not be used as a network cable (whether broadband or LAN), because it is composed of 4 wires, and the plug is called RJ22 port. However, I said earlier that among the 8 lines in the network cable, only 4 of them are really used, so if you know how to use those for communication, you can use the ** line to make an RJ45 head, and it can also be used for network connection, some Netcom or telecom staff will do this, and you can even use 4 of the 8 lines to transmit computer signals, and the other 4 to transmit TV signals.

3) The color arrangement of the twisted pair cable that is really used as a network cable is strictly regulated, you can see from the crystal head, you can see that the order of the color of the line is white-green, green, white-orange, blue, white-blue, orange, white-brown, brown.

Yes, good! The one above is very good!

The question in my heart, that doesn't matter.

The problem in your mind is that dust doesn't cause slowness, and in terms of the network cable itself, the only thing that can cause speed is the length, and the longer it is, the slower, the shorter it is, the faster, but it's only relative, not so absolute.

Whether the cable has anything to do with the speed depends on your bandwidth. You are psychologically acting ......