Ethernet cable, the most inconspicuous part of the computer network, the most easily overlooked parts. When building a network, most people will pay attention to devices such as switches, routers, and network cards, but for ethernet cables, they are generally not too picky.
However, with the expansion of the network scale and the increasing demand for ethernet cables, the importance of ethernet cables is becoming more and more obvious. Let’s take a look at the basics of the next ethernet cable.
Part1: Understand the common sense of the ethernet cable – the type of ethernet cable
1. Common types of ethernet cables
Twisted pairs are commonly found in Category 3, Category 5 and Category 5, Category 6 and the latest Category 7 lines. The former has a thin wire diameter and the latter has a coarse wire diameter. The model number is as follows:
ethernet cable type 1 type line 2 type line 3 type line 4 type line 5 type line super 5 type line 6 type line super 6 type line 7 type line function used in the early 80s telephone cable for the old token net mainly used Supporting 10M ethernet cable for token LAN and Ethernet use Suitable for 100BASE-T and 10BASE-T networks Mainly used for Gigabit Ethernet Suitable for networks with transmission rates higher than 1Gbps Mainly used in Gigabit networks The transmission frequency of megabit Ethernet technology is relatively low. 1MHZ16MHz20MHz100MHz100MHz1MHz~250MHz200～250MHz at least 500MHz The highest transmission rate is lower 4Mbps10Mbps16Mbps100Mbps1000Mbps1Gbps1000Mbps10 Gbps Class 1 line: mainly used for transmitting voice (a type of standard is mainly used before the early 1980s) Phone cable), unlike data transmission.
Class 2 line: The transmission frequency is 1 MHz
which is used for voice transmission and data transmission with a maximum transmission rate of 4 Mbps.It is commonly used in the old token network using the 4 MBPS specification token transfer protocol.
Category 3: A cable specified in the ANSI and EIA/TIA568 standards. The cable has a transmission frequency of 16 MHz and is used for voice transmission and data transmission with a maximum transmission rate of 10 Mbps is mainly used for 10BASE–T.
Category 4 cable: This type of cable has a transmission frequency of 20 MHz.
The data transmission for voice transmission and maximum transmission rate of 16 Mbps is mainly used for token-based LAN and 10BASE-T/100BASE-T.
Category 5 cable: This type of cable increases the winding density, and is a high-quality insulating material with a transmission rate of 100MHz. It is used for voice transmission and data transmission with a maximum transmission rate of 100Mbps. It is mainly used for 100BASE-T and 10BASE- T network. This is the most commonly used Ethernet cables.
Super Category 5: Super Category 5 has low attenuation, low crosstalk
and higher attenuation and crosstalk ratio (ACR) and signal-to-noise ratio (Structural Return Loss), smaller delay error, and greatly improved performance. The Super Category 5 cable is mainly used for Gigabit Ethernet (1000 Mbps).
Category 6 line: The transmission frequency of this type of cable is 1MHz ~ 250MHz. The Category 6 wiring system should have a large margin in the integrated attenuation crosstalk ratio (PS-ACR) at 200MHz, which provides twice the bandwidth of the Super Category 5. The transmission performance of Category 6 cabling is much higher than the Category 5 standard and is best suited for applications with transmission rates above 1Gbps. An important difference between Category 6 and Category 5 is that it improves performance in terms of crosstalk and return loss.
For a new generation of full-duplex high-speed network applications
excellent return loss performance is extremely important. The basic link model is eliminated in the six categories of standards. The cabling standard adopts a star topology. The required cabling distance is: the length of the permanent link cannot exceed 90 m, and the channel length cannot exceed 100 m.
Super Category 6 line: Super Category 6 line is an improved version of Category 6 line. It is also an unshielded twisted pair cable specified in ANSI/EIA/TIA-568B.2 and ISO Class 6/E standard. Main application In a gigabit network. In terms of transmission frequency, like the Category 6 line, it is also 200-250 MHz, and the maximum transmission speed can reach 1 000 Mbps, but it has a great improvement in crosstalk, attenuation and signal-to-noise ratio.
Category 7 line: This line is the latest twisted pair in the ISO 7/F standard
It is mainly used to adapt to the application and development of 10 Gigabit Ethernet technology. But it is no longer an unshielded twisted pair, but a shielded twisted pair, so its transmission frequency is at least 500 MHz, which is more than twice that of Category 6 and Super Category 6 transmission rates. Up to 10 Gbps. Twisted pair can be divided into unshielded twisted pair (UTP=UNSHIELDED TWISTED PAIR) and shielded twisted pair (STP=SHIELDED TWISTEDPAIR). The outer layer of the shielded twisted pair cable is wrapped with aluminum and platinum to reduce radiation, but it does not completely eliminate the radiation. The shielded twisted pair is relatively expensive and difficult to install than the unshielded twisted pair cable. Unshielded twisted pair cable has the following advantages: unshielded jacket, small diameter, saving space occupied; light weight, easy to bend, easy to install; minimize or eliminate near-end crosstalk; flame retardant; Sex and flexibility for structured cabling.
2, the difference between the super five and six ethernet cables
The common ethernet cables in the LAN are mainly twisted pair, coaxial cable, and optical cable. Twisted pair is a data transmission line composed of many pairs of wires. It is characterized by its low price, so it is widely used, such as our common telephone line. It is used to connect to the RJ45 crystal head. It has two kinds of STP and UTP, and we usually use UTP.
Part2: Master the network purchase method to ensure the quality of the Internet
What is the quality of the ethernet cable?
1, pure copper
Pure copper is the best and best quality wire and cable. It is suitable for POE power supply and low resistance to avoid the loss of electricity during transmission.
This kind of ethernet cable is the best ethernet cable. Under the same conditions, the resistance of copper is the second smallest, so you can make high quality wire. It is also suitable for POE power supply, and the small resistance can avoid the loss of electricity during transmission.
2, aluminum wire
The quality of such a ethernet cable is inferior to that of copper wire, but it is not a big problem for short-distance use, so the terminal of the home or small office—-the switch line can select such a line. This type of line is only suitable for short-range POE power supplies because the resistance is larger than copper.
3, copper clad aluminum wire
This kind of ethernet cable is plated with a layer of copper on the outside of the aluminum wire. Because of the skin effect, the conductivity of the aluminum wire is improved. However, such lines are also only suitable for short-range POE power supply, also because of the large resistance.
4, copper clad wire
This kind of ethernet cable is plated with a layer of copper on the outside of the iron wire. Because of the skin effect, the conductivity of the iron wire is improved. However, such lines are not suitable for POE power supply because of the large resistance.
5, iron core wire
Such a ethernet cable has a large resistance and is only suitable for transmission in a short distance and when the network speed is not high. This type of line is not suitable for POE power supply, also because of the large resistance.
6, mixed line
Some of the wires in this type of cable use aluminum wire for aluminum. It is only suitable for short-distance use and can be used for POE power supply. However, when making the crystal head, it must be made in strict accordance with the wire sequence. Otherwise, the copper wire cannot be used for power supply, which will increase the resistance. , affecting the power supply effect. The purchase of the brand by the ethernet cable determines the quality.
Part3, ethernet cable is good, ethernet cable purchase method
1. Identify from the network line
The identification of the three types of lines is “CAT3”, the bandwidth is 10M, and the 10M network is basically eliminated. The identification of the five types of lines is “CAT5”, the bandwidth is 100M, and it is suitable for the network below 100M; the logo of the Super Category 5 is “CAT5E”, with a bandwidth of 155M, is the mainstream product; the label of the six-category line is “CAT6”, with a bandwidth of 250M, which is used to set up Gigabit network, which is the future development trend. The characters printed on the plastic plastic wrap of the real Category 5 line are very clear, sleek and essentially jagged. The quality of the fake prints is poor, some fonts are not clear, and some are severely jagged.
2, feel by hand
If the method of “seeing” is still unrecognizable, the difference between the materials of the true/false type 5/super 5 type line can be further felt by the “touch” method. True Category 5/Super Category 5 cable is softer, mainly to adapt to different network environment requirements. Copper wire is generally used as a wire core in twisted pair cables, which is relatively soft (because some network environments may require ethernet cables for small angle bends). Folding, if the wire is hard, it is easy to cause an open circuit.); Some unscrupulous manufacturers add other metal elements to the copper in order to reduce the cost during production. The wire made is harder, not easy to bend, and is easy to break during use. line.
3, with a knife
In this step, just use scissors to remove the plastic sheath from the outside of a small section to expose 4 pairs of cores. Here we still use the “see” method to further discriminate, the true white 5 / super 5 line 4 pairs of white in the core should not be pure white, but with the core paired with it The color of the line is white, which is mainly for the convenience of the user to distinguish the pair when making the crystal head. The fakes are usually pure white or the color is not obvious. Another point is the winding density of the four pairs of core hdmi cable. The true Category 5/Super Category 5 wire has a moderate density and the direction is counterclockwise. The false line usually has a small density and the direction may be clockwise (less), mainly because it is easier to make, so the production cost is smaller.
4, burn with fire
You can test the twisted pair in a high temperature environment to see if the rubber on the outside of the cable will become soft at 35 ° C to 40 ° C. The genuine cable will not become soft, and the fake will not be necessary; There is also a flame on the outside of the real ethernet cable, while some fake ones do not have flame retardancy, do not meet the safety standards, you may wish to try when buying.
Part4: How to connect the ethernet cable
The difference between home network and office network
Most of the households use twisted pairs (that is, general ethernet cables), which are generally divided into T568A and T568B lines. The information module access mode is divided into T568A module and T568B module. The two terminals are connected. The order is as follows:
T586A mode 1 white green 2 green 3 white orange 4 blue 5 white blue 6 orange 7 white brown 8 brown;
T586B mode 1 white orange 2 orange 3 white green 4 blue 5 white blue 6 green 7 white brown 8 brown.
There are currently several types of existing ethernet cables on the market: Category 5, Category 4, Category 5 and Category 6. The types, performance, quality and speed of the lines are different. The best selling is that the five types of lines are cheap and practical. Users can filter according to their needs and choose the type that suits them best. Some line types also have a shielding function, which can be grounded, mainly different in crystal heads, and is suitable for collective use by large enterprise units.
The use of the ethernet cable of the office is mainly practical and artistic. If there is no network port, the wiring should be as close as possible to the ceiling. The integrated wiring should be used. The casing should be used in the wall to prevent the damage of the line. To prevent moisture from getting wet or blasting.
Home network cabling advice
Before conducting network cabling, you should first understand your own living environment and the use of each room. Where can you embed and embed? Where can you not? At the same time, we must understand the network needs of the family, and where should we go online? Where do you want to watch TV? I have to count in my heart. Draw a sketch of the design according to your own vision, and then determine the location of the distribution box and the splitter according to the power distribution box, cable TV inlet and telephone line, and the location of the ethernet cable entry. Generally, the distribution box should not be easily moved; the wiring box of the telephone line and the network line should be selected as a place that does not affect the appearance and is convenient to operate. Considering that the router and the switch should be placed, a larger wiring box should be designed; The TV is designed with a box that can hold two TV splitters at the entrance. It is recommended that you use parallel wiring, and the telephone line and ethernet cable are respectively 4-core and 8-core (Category 5). For convenience, the telephone line and the ethernet cable are worn in the same PVC pipe (theoretically, the telephone line and the network line) They should be routed separately with a distance of 10cm to avoid mutual interference. Considering that the time spent on the home phone and the network is short, it will not cause large interference. If there are multiple computers to be connected to the Internet at the same time, just add a broadband router or switch to the main wiring.
Office network cabling recommendations
1. Comprehensive: Office wiring needs to meet the transmission requirements of various analog or digital signals, and combine all the language, data, image, and monitoring equipment wiring in a standard wiring system, between the equipment and the information outlet. Simply plug them in with a standard cable through the standard interface.
2. Reliability: The products used in the office wiring system must be certified by international organizations. The design, installation and testing of the wiring system are based on ANSI EIA/TIA 568A and GB/T50311-200, and follow the domestic wiring specifications and test specifications. .
3. Flexibility: How many information points are used in each office location, office wiring not only meets the current needs of users, but also meets users’ expectations for future information systems; and data and voice twisted pair cabling should be interchangeable. Form a complete wiring system.
4. Reasonability: The wiring direction of the office strong and weak electricity should be reasonably matched, not interfere with each other, and the appearance should be beautiful; the user should use the power, telephone and ethernet cable of the computer at the same time to facilitate operation and facilitate future operation and maintenance.
5, the complementarity of wired and wireless: according to the specific building environment and office requirements of the building, long-term or temporary use of the network, etc., decide whether to use wired wiring or wireless; in general, it is to combine wired and wireless to play their respective The speciality to achieve the purpose of our online office.
ethernet cable socket connection
Use a stripping tool or a crimping tool to strip the outer sheath of the twisted pair about 10 cm in length to expose four pairs of twisted pairs. Start to hit the line, do not disassemble the line pairs first, and then disassemble the corresponding line pairs before pushing them into the wire column. Select our preferred line-sequence mode according to the color code indicated on the information module (in a wiring system, it is best to use only one line-sequence mode, otherwise it will be confused, and the network will be difficult to check). After pressing all the wires into each slot, press the module and the wire with the tool, press down firmly, clamp the cable into the module, and cut off the excess head. It is to install the wired information module on the 86 box panel, so that the wall cable socket is installed.