What is Twisted Pair? How to classify it?

No way. Eldest brother.

You don't even know about twisted pairs.

How do you get online?

Twisted pair refers to network cables, which can be divided into unshielded twisted pairs.

and shielded twisted pairs, which are now mainly Class 6.

line, according to the electrical classification of class 1, class 2, class 3, class 4, class 5, super class 5, class 6, class 6, class 7, standard 568b: white orange - 1, orange - 2, white green - 3, blue - 4, white blue - 5, green - 6, white brown - 7, brown - 8

Standard 568a: White-green--1, green--2, white-orange--3, blue--4, white-blue--5, orange--6, white-brown--7, brown--8

Cross lines. Refers to: a twisted pair with a 568A standard on one end and a 568b standard on the other end. A direct cable is a twisted pair that is either 568A or 568B at both ends.

A twisted pair is made up of 4 sets of copper wires encapsulated in an insulated jacket. The reason why they are wound with each other is that when there is an electric current (in fact, a data stream) passing through the metal wire, an electromagnetic field will be generated, and when the positive and negative signal lines are wound, the positive and negative magnetic fields generated by the two will cancel each other out and reduce the interference of the signal.

Classification and application of twisted pairs.

At present, twisted pair cables can be divided into unshielded twisted pair (UTP: unshildedtwistedpair) and shielded twisted pair (STP: shieldedtwistedpair).

Please refer to the details.

The common twisted pair cables are Category 3 cables, Category 5 cables and Category 5 cables, as well as the latest Category 6 cables.

The former has a thin wire diameter and the latter has a thick wire diameter, and the models are as follows:

1) A class of cables: mainly used for voice transmission (a class of standards are mainly used for ** cables before the early eighties), different from data transmission.

2) Category 2 line: the transmission frequency is 1MHz, which is used for voice transmission and data transmission with a maximum transmission rate of 4Mbps, which is commonly found in the old token network that uses the 4Mbps specification token passing protocol.

3) Category III cable: refers to the cable currently specified in the ANSI and EIA TIA568 standards, the transmission frequency of the cable is 16MHz, which is used for voice transmission and data transmission with a maximum transmission rate of 10Mbps is mainly used for 10BASE-T.

4) Category IV wire: The transmission frequency of this type of cable is 20MHz, which is used for voice transmission and data transmission with a maximum transmission rate of 16Mbps, which is mainly used for token-based LAN and 10BASE-T 100BASE-T.

5) Category 5 wire: This type of cable increases the winding density, and is coated with a high-quality insulating material, with a transmission rate of 100MHz, which is used for voice transmission and data transmission with a maximum transmission rate of 10Mbps, mainly used for 100Base-T and 10Base-T networks. This is the most commonly used Ethernet cable.

6) CAT5e line: CAT5 has reduced attenuation, less crosstalk, and has a higher attenuation-to-crosstalk ratio (ACR) and signal-to-noise ratio (structuralreturnloss), smaller time delay difference, and the performance has been greatly improved. Category 5 cables are mainly used for Gigabit Ethernet (1000Mbps).

7) Category 6 cable: The transmission frequency of this type of cable is 1MHz 250MHz, and the comprehensive attenuation crosstalk ratio (PS-ACR) of the Category 6 cabling system should have a large margin at 200MHz, which provides 2 times the bandwidth of Category 5.

It can be divided into two categories: shielded twisted pair STP and unshielded twisted pair UTP, according to the electrical performance, twisted pair can be divided into: class 1, class 2, class 3, class 4, class 5, super class 5, class 6, class 6, class 7, a total of 9 types of twisted pair type.

Twisted pairs are divided into shielded twisted pair and unshielded twisted pair.

1. Shielded twisted pair.

It is a copper twisted pair that is widely used for data transmission. In terms of physical structure, the shielded twisted pair has more full shielding and or wire-to-pair shielding than the unshielded twisted pair, which reduces attenuation and noise through shielding, thereby providing a cleaner electronic signal and longer cable length, but the shielded twisted pair is more expensive, heavier and not easy to install.

2. Unshielded twisted pair.

It is a kind of data transmission line, which is composed of four pairs of transmission lines of different colors, which is widely used in Ethernet and ** cables. The unshielded twisted pair cable has an unshielded jacket with a small diameter, which saves the space occupied and has a low cost; Light weight, easy to bend, easy to install; Flame retardant; It has the advantages of independence and flexibility. In the integrated wiring system, unshielded twisted pair is widely used.

This is the answer on my school's computer networking book.

The main characteristics and applications of various types of twisted pairs.

Type: Class 1, Class 2, Class 3, Class 4, Class 5, Super Class 5, Class 6.

Transmission rate bps: 20k, 1m, 10m, 20m, 100m, 155m, 200m

Transmission signal types: analog signal, analog signal and 1m digital signal, analog signal and digital signal, analog signal and digital signal, analog signal and high-speed digital signal, analog signal and high-speed digital signal, analog signal and high-speed digital signal.

Applications: Lines, General Communication Lines, Ethernet & Token Ring, Token Ring, High Speed Ethernet, ATM, FDDI, High Speed Ethernet, ATM, High Speed Ethernet, ATM.

That's it. The type of transfer rate and application order are corresponding.

Structurally, it is divided into: shielded twisted pair and unshielded twisted pair.

It is divided into 5 categories in terms of use: cat1, cat2, cat3, cat4, and cat5

In the past, CAT3 and CAT4 were mostly used for 10M network formation, while CAT5 was mostly used for 100M networks. Now cat5 (Cat5 line) is mostly used.

1) Class 1 line (cat1):

The maximum frequency bandwidth of the cable is 750kHz, which is used for alarm systems, or only for voice transmission (a class of standards is mainly used for ** cables before the early eighties) and is not used for data transmission.

2) Class 2 line (cat2):

The maximum frequency bandwidth of the cable is 1MHz and is used for voice transmission and data transmission at a maximum transmission rate of 4Mbps, which is common in older token networks that use the 4Mbps specification token passing protocol.

3) Category 3 line (cat3):

Refers to the cable specified in the ANSI and EIA TIA568 standards, the cable has a transmission frequency of 16MHz, a maximum transmission rate of 10Mbps (10Mbits), mainly used in voice, 10Mbit S Ethernet (10Base-T) and 4Mbit S Token Ring, the maximum network segment length is 100M, and the connector in the form of RJ has been faded out of the market.

4) Category 4 line (cat4):

This type of cable has a transmission frequency of 20MHz and is used for voice transmission and data transmission at a maximum transmission rate of 16Mbps (referring to the 16Mbit S Token Ring), mainly for token-based LANs and 10BASE-T 100BASE-T. The maximum network segment length is 100 m, and the connector in the form of RJ is not widely used.

5) Cat5 line (cat5):

This kind of cable increases the winding density, the jacket is a high-quality insulating material, the highest frequency bandwidth of the cable is 100MHz, the maximum transmission rate is 100Mbps, for voice transmission and the maximum transmission rate of 100Mbps data transmission, mainly used for 100BASE-T and 1000BASE-T networks, the maximum network segment length is 100M, and the connector in the form of RJ.

6) Cat5e line:

Category 5 has reduced attenuation, less crosstalk, and has a higher attenuation-to-crosstalk ratio (ACR) and signal-to-noise ratio (SNR), and a smaller time delay difference, and the performance has been greatly improved. Category 5 cables are mainly used for Gigabit Ethernet (1000Mbps).

7) Category 6 line (cat6):

The transmission frequency of this type of cable is 1MHz 250MHz, and the Category 6 cabling system should have a large margin for the Combined Attenuation Crosstalk Ratio (PS-ACR) at 200MHz, which provides 2 times the bandwidth of Category 5e. The transmission performance of Category 6 cabling is much higher than that of Category 5e standards, and it is most suitable for applications with transmission rates higher than 1Gbps.

8) Super Class 6A or 6A (Cat6A):

The transmission bandwidth of this type of product is between Category 6 and Category 7, the transmission frequency is 500MHz, the transmission speed is 10Gbps, and the standard outer diameter is 6mm. Like the seven types of products, the country has not yet issued a formal testing standard, but there are such products in the industry, and each manufacturer announces a test value.

9) Category 7 line (cat7):

The transmission frequency is 600MHz, the transmission speed is 10Gbps, the standard outer diameter of a single wire is 8mm, and the standard outer diameter of a multi-core wire is 6mm.

Twisted pairs are divided into shielded twisted pair and unshielded twisted pair.

1. Shielded twisted pair has a metal shield between the twisted pair and the outer insulating envelope. Shielded twisted pair wires are divided into STP and FTP, STP means that each wire has its own shielding layer, while FTP only works when the entire cable is shielded and both ends are properly grounded. Therefore, the whole system is required to be shielded devices, including cables, information points, crystal heads and distribution frames, etc., and the building needs to have a good grounding system.

2. Unshielded twisted pair cable is a kind of data transmission line, which is composed of four pairs of transmission lines of different colors, which is widely used in Ethernet and first-class cables.