Application of 10 GB Ethernet and twisted pair copper cable

Regardless of the final minimum copper platform, the complexity of the encoding system is a major obstacle for source equipment manufacturers. For cable and connector personnel and physical layer equipment installers, the question is more about what restrictions will this bring to the cabling facilities and what installation and test parameters will be required.

The Working Group has made a lot of discussions to solve the problem of external crosstalk. To eliminate most of the crosstalk, we twist the cables together and change the twisting distance between the cables to reduce the potential impact of the wires on the internal parallel wires. Another method requires balanced transmission. Due to the high transmission frequency of category 6 cables, the problem of external crosstalk is raised during the development of cables and external hardware specifications. It is recognized that external crosstalk is more likely. The recommended range in the industry is MB ~ A higher frequency and encoding system of MHz, enabling Gbps bandwidth on each of the four line pairs to achieve 10 Gbit/s throughput on the channel. Various installed cable models have been designed in the industry to measure the typical foreign crosstalk produced at these frequencies when multiple cables are bundled very close together. However, there are still many problems to be solved:

Which wiring facility can handle this speed with reliable information transmission?

How far does it support?

Is it economical?

A working group has been set up in the industry to check whether the implementation of 10GbE on copper cables is feasible and the actual situation. For this team, the above issues are increasingly becoming the main controversial area. We will focus on physical layer design considerations to assess whether the twisted pair copper cable is expected to support 10GbE.

The team members have raised external crosstalk issues and put forward a large number of test and analysis models. We will define the external crosstalk as the component at the bottom of the end, which is also the crosstalk that occurs throughout the cable cabling. External crosstalk has become one of the many factors to consider when examining the channel performance of a negligible telephone line in the past. We recommend that you do not create a perfect cable bundle in cabling. Instead, you should use a random twist distance in the cables in the cabling group. This helps avoid overlong parallel cabling on different cables to reduce the impact of external crosstalk.

During the evaluation, it is very important to examine the typical attenuation crosstalk ratio (ACR) of the cable category to be evaluated under different lengths and extended frequencies ). The category of cables currently under investigation includes cat5e (Class D), cat6 (Class E), and cat7 (Class F) cables. In the 10GbE recommendation for the first twisted pair copper cable, the team considered the basic platform of Category 5 (Class D ). However, the proposal made by the ISO team shows that cat6 cabling will develop rapidly in the 10GbE standard development process, which should include such a platform with higher performance. The standards are still in the early stages of development. Different IEEE experts are currently submitting reports based on many issues, some of which are as follows:

External crosstalk, bundled cables, distribution frames and adjacent sockets in active devices are very close;

ACR of the channel category to be evaluated;

Transmission System and voltage level;

Radiation problems;

Study on average channel length of the horizontal subsystem in typical commercial office environments.

The Research on the channel length is very interesting, and it is affected by the preliminary investigation results related to different channel capabilities. In the early stages of the study, the project was to examine how far 10GbE can be supported in copper on medium in question. Some demos are not optimistic about the recommended cabling categories below:

Cat5e (Class D), up to 20 meters;

Class 6 (Class E), up to 30 meters;

Class 7 (Class F), close to 100 meters.

As the world tends to have six (Class E) Basic platforms and their development trends, we are concerned about whether cat6 cabling can support 10GbE speed. In standard commercial cabling, the distance between most horizontal links is less than 60 meters. It is recommended that 10 GbE be supported at least 5-100 m in cat6 cabling, and m in seven cabling. In addition, we are still investigating whether the shielded cat6 cabling and enhanced unshielded cat6 (sometimes called the E + class) can implement 10GbE within 100 meters. External crosstalk is still A major issue and the discussion is currently centered on A-NEXT, A-PSNEXT, A-FEXT and A-PSFEXT. The tia tr 42 committee in charge of cabling Affairs is developing an enhanced 6-class platform with its performance parameters extended to 625 MHz. The results show that cat6 cabling with a distance of at least 55 meters is the preferred choice.

1. 10 Gbit/S Ethernet test challenges twisted pair cabling Environment
2. After passing the 10 Gigabit copper cable standard