Nowadays, with the continuous emergence of new services such as cloud computing, big data, and 5G, the scale of data centers continues to expand, and their architecture and cabling are becoming more and more complex. The lightweight and gradual reduction of optical fiber makes the backbone network equipment and the demand for optical fiber is also growing. The proportion of optical fiber in large data centers is as high as 70%, which is much higher than that of copper cable. Many twisted pair practitioners are worried that copper cable will be completely replaced by optical fiber. Recently, I went through the specifications and did a simple market demand survey. Based on the latest international standards ISO11801:2017 and ANSI/TIA-TIA-568.2-D as the main data center cabling application technology evolution and international standard update content . After refining and sorting out the application data of China's future data centers in various aspects such as the application direction of the future data center, it is found that Cat.8 40G can fill the gap in the 40G transmission application of copper twisted pair.
Although, driven by the data center's demand for higher bandwidth, optical fiber has a larger share in data center deployment due to the advantages of higher transmission rate and greater bandwidth, especially the backbone application network; but in fact, Copper cables will still be an indispensable part of the data center, and in special environment applications such as voice transmission and power supply, in addition to voice signal transmission and wireless access, POE power supply systems and other power supply applications, optical fiber Cannot replace copper cables.
First, because copper cables are different from optical fibers in that they transmit data through electrical pulses and can support voice signals. Therefore, copper cables can be used for voice transmission, but optical fibers cannot.
Second, because the glass fiber used in the optical fiber cannot conduct electricity, the copper in the copper cable can conduct electricity.
Therefore, copper cables can supply power while performing data connections, and are widely used in wireless access, POE power supply systems, LED-based power systems, etc. Copper cables are cables that cannot be replaced by optical fibers. TIA standard-TIA The indispensable application scenarios are described in detail in 568.2-D:
1. The copper cable section mentions the relevant content and application requirements of 25GBase-T and 40GBase-T based on Cat8.
2. The double coaxial balanced cable DAC part supplements the contents of 100GBase-CR2, 100GBase-CR4 and 200GBase-CR4.
3. The backbone optical fiber technology of the data center adds 200G/400G multiple types of optical fiber transceivers based on IEEE802.3bs and IEEE802.3cm applications, application distance and other definitions, etc. The latest OM5 optical fiber technology is introduced this time.
4. Introduced the latest IEEE802.3bt POE standard, which will be used in data center buildings in various intelligent systems.
5.Defines the requirements for the highest attenuation value based on the application of each single-mode and each multi-mode fiber from 1GB-64GB in the SAN network based on FCIA.
6. The chapter of design principles focuses on the different redundant connection models defined by international standards under different architectures of EOR and TOR network scales.
7. Added analysis of the advantages and disadvantages of various network architectures such as tree type, leaf-spine type, and full network type.
8. Recommendations for the application scenarios of the network and wiring architecture of four types of data centers, such as enterprise data centers, IDC, micro modules, and EDGE, for different data center types.
In addition, in the TIA-568.2-D standard, Modular Plug Termination Link (MPTL) is used as an option for connecting devices. This move will promote the growth of RJ45 copper cable applications, especially in surveillance systems using IP cameras. At the same time, 28AWG specification network jumpers have been added to the appendix of this specification, and smaller specifications of copper cables will help air circulation and space utilization, so that it can be developed in high-density applications.
There are many types of copper cables on the market today, such as CAT-5e, CAT-6, CAT-6, CAT-7 and CAT-8 network jumpers, and different types of copper cables have different wiring applications, as follows:
1. Category 5 network jumper
The Cat5e network jumper (Cat5e network cable) was developed by TIA/EIA in 2001. It has low attenuation, less crosstalk, a maximum bandwidth of 100MHz, and a maximum transmission rate of 1000Mb/s. It is backward compatible. As far as the five types of network cables are concerned, its performance has been greatly improved, with higher attenuation to crosstalk ratio (ACR) and channel to noise ratio (SNR), as well as smaller delay errors. Category 5e network jumpers are suitable for 100M and Gigabit Ethernet, and are commonly used in home networks or indoor wiring.
2. Category 6 network jumper
The bandwidth of the Category 6 network jumper (ie Cat6 network cable) is 250MHz, and the maximum transmission rate is 10Gb/s. Compared with Category 5 network jumpers, Category 6 network jumpers have a better internal structure. Among them, a cross skeleton is used inside, and the twisting distance of the four pairs of twisted pairs is smaller, which makes Category 6 network jumpers in crosstalk and return. The performance of wave loss and other aspects has been improved, and the transmission performance is much higher than that of Category 5 network jumpers, which is more suitable for applications with transmission rates greater than 1Gbps. In addition, under normal circumstances, the maximum transmission distance of Category 6 network jumpers does not exceed 55 meters.
3. Super Category 6 network jumper
Super Category 6 network jumper (ie Cat6a network cable) is an improved version of Category 6 network jumper, its bandwidth is twice that of Category 6 network jumper, the transmission frequency can reach 500MHz, and the maximum transmission rate is 10Gb/s. Due to the high-quality structure of the Super Category 6 network jumper, it helps to eliminate alien crosstalk (AXT), so it can support a distance of up to 100 meters. In addition, compared with Category 6 network jumpers, the conductor material of Super Category 6 network jumpers is thicker, which is more suitable for industrial environments.
4. Seven types of network jumpers
The seven types of network jumpers (ie, Cat7 cable) have a transmission frequency of up to 600 MHz, and support a transmission rate of 10Gbps within a transmission distance of 100 meters, which is suitable for adapting to 10 Gigabit Ethernet. Compared with the previous generations of network jumpers, the seven types of network jumpers have strong shielding properties, which can effectively reduce attenuation, and are suitable for the connection of switches, patch panels and other equipment in high-density data centers. It is worth mentioning that the transmission rate of the seven types of network jumpers can be as high as 40Gbps at a transmission distance of 50 meters, and even up to 100Gbps at a transmission distance of 15 meters. At present, because the seven types of network jumpers are not flexible enough and not easy to manage, they have not been popularized for the time being.
5. Eight types of network jumpers
Category 8 network jumpers (ie Cat8 cable) are the next-generation twisted-pair copper cable standard specified by ANSI/TIA-568-C.2-1, which can support a bandwidth of up to 2000MHz and a transmission rate of up to 40Gb/s, but Its maximum transmission distance is only 30m, so it is generally used for the connection of servers, switches, patch panels and other equipment in short-distance data centers. Since the eight types of network cables are specially designed for 25GBASE-T and 40GBASE-T applications, they are especially suitable for the interconnection of data center switches to servers.
There is no doubt that copper cables still occupy an important position in applications such as voice transmission, indoor networks, horizontal wiring, and POE systems, and will not be completely replaced by optical fibers. Copper technology is still under continuous research and development, especially CAT8 And the popularization and application of CAT9 can already meet the demand for more equipment connections in the future. Therefore, you do not need to worry about the rapid elimination of copper cables in the era.