The difference between CAT5E, CAT6 and CAT6A

In the past 100M Fast Ethernet era, our integrated wiring system has been able to meet the network applications under this bandwidth using Category 5 wiring, but with the development of computer network technology and various endless network applications (such as: video Applications of high-bandwidth data services such as conferences and online high-definition video) have brought new demands on network bandwidth. At this time, 1000M Ethernet applications appeared. In order to meet 1000M Ethernet applications, the performance of the original CAT5 wiring system was carried out. Optimization At this time, a super five-category wiring system with slightly better performance than CAT5 wiring appeared. Therefore, in the past 10 years, the CAT5 wiring system has basically lost its market vitality and faded out of the integrated wiring market.

In the field of Ethernet applications, there are two network application standards for 1000M Ethernet applications. One is the 1000BASE-T Gigabit Ethernet standard approved by the IEEE Standardization Committee in 1999 during the initial upgrade of Ethernet from 100M to 1000M. The application standard is specifically designed to be used in existing Category 5 copper wire systems. It is proposed to meet the demand for the rapid expansion of bandwidth without changing the existing wiring. The technology is based on 4 pairs of twisted pairs, each pair of lines simultaneously receive and send signals, and uses extremely complex 5-level coding technology, anti-interference and echo suppression technology. This technology makes the circuit design of the network interface of the switch and the network card very complicated, which is not conducive to reducing the size and heat dissipation of the device, and the production cost is also high.

Another Gigabit Ethernet application standard is the 1000BASE-TX Gigabit Ethernet standard reissued by the TIA / EIA-854 Standardization Committee after the IEEE Standardization Committee released 1000BASE-T. This technology is also based on four pairs of twisted pairs , But it is sent on two pairs of lines, and two pairs of lines are received (this is similar to the way in which 100Base-TX Fast Ethernet applications use one pair of lines to send data and the other one pair of lines to receive data). Since each pair of cables does not transmit bidirectionally, the crosstalk between the cables is greatly reduced, and the encoding method is relatively simple. This technology requires relatively low network interface, does not require very complicated circuit design, and reduces the cost of the network interface. However, due to the reduced efficiency of using cables (two-pair line reception, two-pair line transmission), to achieve a transmission rate of 1000mbps, the physical bandwidth of the copper transmission medium must be required to exceed 100MHz, that is, in Category 5 and Super 5 This type of cabling system will not support this type of network application.

Therefore, due to the difference in wiring transmission performance requirements of the two Gigabit Ethernet standards at that time, all integrated wiring manufacturers were forced to launch Category 6 wiring systems with stronger anti-interference ability and better transmission performance than Category 5 wiring. Next, briefly explain the difference in performance between CAT5E and CAT6 wiring system products:

1. CAT5E wiring physical bandwidth: 100MHz, CAT6 wiring physical bandwidth: 250MHz;

Note: The larger the physical bandwidth, the higher the transmission rate supported.

2. CAT5E cable usually uses 24AWG wire gauge (copper core diameter: about 0.51mm), CAT6 cable usually uses 23AWG wire gauge (copper core diameter: about 0.57mm);

Note: The thicker the copper core diameter, the better the conduction performance and the smaller the signal attenuation on the line. In the PoE application field, 23AWG has an absolute advantage in energy transfer over 24AWG.

3. The maximum data transmission rate supported by CAT5E wiring theory is 1200Mbps, and the maximum data transmission rate supported by CAT6 wiring theory is 2400Mbps;

Note: The higher the data transfer rate, the greater the physical bandwidth.

4. 10GBASE-T 10 Gigabit Ethernet application standard not supported by CAT5E cabling, 10GBASE-T Ethernet application standard supported by CAT6 cabling, but the transmission distance is limited and cannot exceed 37 meters.

Note: Category 6 cabling system is still barely able to meet the needs of 10 Gigabit Ethernet applications over short distances, but Category 5 systems cannot be supported.

5. CAT6 cable usually uses a cross-frame structure to reduce crosstalk between pairs, and its (NEXT) near-end crosstalk performance index is 5-10dB higher than the CAT5E performance index without a skeleton structure in the range of (1-100MHz);

Note: Minimizing crosstalk between wire pairs is the most important basic prerequisite for stable and high-speed transmission of data information in wiring systems.

Comprehensively comparing the differences between the above two levels of wiring systems, the Category 6 wiring system is not only much higher than the Category 5 wiring system in terms of physical and electrical performance, but also much higher than the Category 5 wiring system in terms of high-speed data and stable transmission. At the same time, with the continuous maturity of the Category 6 wiring market, the large-scale promotion of Category 6 products has driven the production of large-scale Category 6 products, making the price of Category 6 wiring products no longer much higher than the prices of Category 5 products.

Just now when we analyzed the difference in performance between CAT5E and CAT6 cabling system products, we also talked about the application of Category 6 cabling on 10 Gigabit Ethernet. In fact, the application standard of 10 GBASE-T for 10 Gigabit Ethernet was as early as September 2006. It was officially released in IEEE802.3an by the IEEE Standards Committee. In order to meet the requirements of 10 Gigabit Ethernet applications, major cabling standardization organizations (such as: International Standardization ISO11801, the United States TIA568B) released a new cabling system standard for 10 Gigabit Ethernet applications in 2008, that is, Super Category 6 integrated cabling standard. The performance of the Super Category 6 wiring system is much higher than the original Category 6 wiring system in terms of resistance to electromagnetic interference and transmission performance. Next, here is a brief explanation of the performance differences between CAT6 and CAT6A cabling system products:

1. CAT6 wiring physical bandwidth: 250MHz, CAT6A wiring physical bandwidth: 500MHz;

Note: The larger the physical bandwidth, the higher the transmission rate supported.

2. CAT6 cable loop resistance (at 20 ℃) ​​155 ohm / km, NVP value: 69%;

CAT6A cable loop resistance (at 20 ℃) ​​150 ohms / km, NVP value: 76%;

Note: The smaller the copper core loop resistance, the better the conduction performance and the smaller the signal attenuation on the line. The cable NVP value is the percentage of the electrical signal transmission rate in the copper medium equal to the speed of light in vacuum. The higher the NVP value, the faster the electronic signal is transmitted in the medium.

3. The 10GBASE-T 10 Gigabit Ethernet application standard supported by CAT6 cabling, but the transmission distance is limited and cannot exceed 37 meters (and an external crosstalk test needs to be added to re-evaluate the performance of Category 6 cabling systems against external electromagnetic interference). The 10GBASE-T Ethernet application standard that CAT6A cabling can support, meets the standard application of 100 meters range, no additional alien crosstalk test.

Explanation: The CAT6A type wiring system can fully meet the needs of 10 Gigabit Ethernet applications at a distance of 100 meters. There are many defects in the CAT6 type 6 wiring system to transmit 10 Gigabit Ethernet.

4. CAT6A cable usually adopts the method of aluminum foil shielding plus aluminum foil overall shielding to achieve extremely good shielding effect against external electromagnetic interference and crosstalk between wire pairs. The crosstalk between the six types of unshielded twisted pairs of the cross-frame structure is 15-35dB higher in the range of (1-250MHz).

Note: Minimizing crosstalk between wire pairs and avoiding external electromagnetic interference on the cable are the most important basic prerequisites for the stable and high-speed transmission of data information in the wiring system.

The integrated wiring system has been developed for more than 20 years. With the popularity of network applications in various fields, the number of ports has increased dramatically. And with the continuous development of information technology, users have higher and higher requirements for network speed. In order to support the development of network speed, the network wiring system has also been extended from the initial three types of systems to support 10 Gigabit transmission today. CAT6A (category 6), can provide a transmission rate of 10 Gigabit 10Gbps. So for now, the transmission performance of copper cabling is no longer the bottleneck of the application.