In the past era of 100m Fast Ethernet, our generic cabling system can meet the network application under this bandwidth by using five types of wiring. However, with the development of computer network technology and various network applications (such as video conference, online high-definition video and other high bandwidth data services applications), new requirements for network bandwidth are put forward, At this time, the application of 1000m Ethernet appeared. In order to meet the application of 1000m Ethernet, the performance of the original CAT5 cabling system was optimized. At this time, the performance of CAT5 cabling system was slightly better than that of CAT5 cabling system. Therefore, in the past 10 years, CAT5 cabling system basically lost its vitality in the market and faded out of the generic cabling market.
In the field of Ethernet application, there are two kinds of network application standards for 1000m Ethernet applications. One is the 1000BASE-T Gigabit Ethernet standard approved by IEEE Standardization Committee in 1999 at the initial stage of Ethernet upgrading from 100m to 1000m. This application standard is specially designed for use in existing category 5 copper wire systems, It is proposed to meet the demand of rapid expansion of bandwidth without changing the existing wiring. The technology is based on 4 pairs of twisted pair wires, each pair of lines sends and receives signals at the same time, and adopts extremely complex 5-level coding technology, anti-interference and echo suppression technology. This technology makes the circuit design of the network interface between the switch and the network card very complex, which is not conducive to reducing the equipment size and heat dissipation, and the production cost is also high.
Another Gigabit Ethernet application standard is the 1000Base-TX Gigabit Ethernet standard re issued by TIA / eia-854 Standardization Committee after IEEE Standardization Committee issued 1000base-t. this technology is also based on four pairs of twisted pair, but it is sent by two pairs of wires and received by two pairs of wires（ This is similar to using one pair of wires to send data and another pair of wires to receive data in 100base TX Fast Ethernet Applications). Because each pair of cables does not carry out two-way transmission, the crosstalk between cables is greatly reduced, and the encoding method is relatively simple. This technology requires less network interface, does not need very complex circuit design, and reduces the cost of network interface. However, due to the reduced efficiency of using cables (two pairs of wires receive and two pairs of wires transmit), the physical bandwidth of copper cable transmission media must exceed 100MHz to achieve the transmission rate of 1000Mbps. That is to say, the cabling system of category 5 and category 5 will not be able to support this type of network application.
Therefore, due to the differences in the transmission performance requirements of the two Gigabit Ethernet standards at that time, all generic cabling manufacturers launched category 6 cabling system with stronger anti-interference ability and better transmission performance than category 5 Cabling.
The difference between CAT5e and CAT6 cabling system
Difference 1:
CAT5e cabling physical bandwidth: 100MHz
CAT6 cabling physical bandwidth: 250MHz
Note: the larger the physical bandwidth, the higher the transmission rate.
Difference 2:
The cable diameter is about 245 AWG;
CAT6 cable usually adopts 23AWG wire gauge (copper core diameter: about 0.57mm);
Conclusion: the thicker the copper core diameter, the better the conductivity, and the smaller the signal attenuation on the line. In Poe application field, 23AWG has an absolute advantage over 24awg in energy transfer.
Difference 3:
The maximum data transmission rate supported by CAT5e cabling theory is 1200mbps;
CAT6 cabling theory supports a maximum data transmission rate of 2400mbps;
Note: the higher the data transmission rate, the greater the physical bandwidth.
Difference 4:
10GBASE-T 10 Gigabit Ethernet application standard not supported by CAT5e cabling,
CAT6 cabling can support the 10GBASE-T Ethernet application standard, but the transmission distance is limited to 37 meters.
Note: Category 6 cabling system can barely meet the demand of 10 Gigabit Ethernet Application in short distance, while category 5 cabling system cannot support it.
Difference 5:
CAT6 cable usually adopts cross frame structure to reduce crosstalk between pairs, and its (next) near end crosstalk performance index is 5-10db higher than that of CAT5e without skeleton structure in the range of (1-100mhz);
Note: minimizing the crosstalk between lines is the most important basic premise for stable and high-speed transmission of data information in the cabling system.
The differences between the above two levels of cabling systems are compared
Category 6 cabling system is not only much better than category 5 Cabling System in physical and electrical performance, but also much higher than category 5 Cabling System in terms of high speed and stable data transmission. At the same time, with the continuous maturity of category 6 cabling market, the large-scale promotion of category 6 products drives the large-scale production of category 6 products, making the price of category 6 cabling products no longer much higher than that of category 5.
When we analyzed the performance differences between CAT5e and CAT6 cabling systems, we also talked about the application of category 6 cabling in 10 Gigabit Ethernet. In fact, the application standard of 10GBASE-T for 10 Gigabit Ethernet was officially released by IEEE standards committee in ieee802.3an as early as September 2006. In order to meet the application requirements of 10 Gigabit Ethernet, major wiring standardization organizations (such as: International Standardization iso11801, tia568b of the United States) issued a new cabling system standard for 10 Gigabit Ethernet Applications in 2008, namely the super six generic cabling standard. The performance of category 6 cabling system is much higher than the original category 6 cabling system in terms of anti electromagnetic interference and transmission performance.
The difference between CAT6 and cat6a cabling system
Difference 1:
CAT6 cabling physical bandwidth: 250MHz
Cat6a cabling physical bandwidth: 500MHz;
Note: the larger the physical bandwidth, the higher the transmission rate.
Difference 2:
CAT6 cable loop resistance (at 20 ℃) 155 ohm / km, NVP value: 69%;
Cat6a cable loop resistance (at 20 ℃) 150 ohm / km, NVP value: 76%;
Note: the smaller the copper core loop resistance is, the better the conduction performance is, and the smaller the signal attenuation on the line is. The NVP value of the cable is the percentage of the transmission rate of electrical signal in copper medium equivalent to the speed of light in vacuum. The higher the NVP value, the faster the transmission speed of electronic signals in the medium.
Difference 3:
CAT6 cabling supports 10GBASE-T 10 Gigabit Ethernet application standard, but the transmission distance is limited to 37 meters (and external crosstalk test is needed to re evaluate the performance of category 6 cabling system against external electromagnetic interference).
Cat6a cabling can support 10GBASE-T Ethernet application standard, which can meet the standard application of 100m range without additional external crosstalk test.
Description: cat6a cabling system can fully meet the application requirements of 10 Gigabit Ethernet at 100 meters distance, and there are many defects in CAT6 class 6 cabling system transmitting 10 Gigabit Ethernet.
Difference 4:
Cat6a cable is usually shielded to aluminum foil plus aluminum foil total shielding, which achieves excellent shielding effect of external electromagnetic interference and line to line crosstalk. The crosstalk between six kinds of unshielded twisted pair pairs with cross frame structure is 15-35db higher than that of the six types of unshielded twisted pair in the range of (1-250MHz).
Note: minimizing the crosstalk between lines and avoiding the external electromagnetic interference of cables is the most important basic premise for stable and high-speed transmission of data information in the wiring system.
The development of generic cabling system has been more than 20 years. With the popularization of network application in various fields, the number of ports increases sharply. And with the continuous development of information technology, users have higher and higher requirements for network operation speed. In order to support the development of network speed, the network wiring system has also extended from the initial three types of systems to cat6a (super-6 category) which supports 10 Gigabit transmission, which can provide 10 Gbps transmission rate. So at present, the transmission performance of copper cabling is no longer the bottleneck of application.