Should i use 568a or 568b

With the only difference between the two standards is the placement of cable pairs on set pins, functionally both standards are the same. Pinout Positions Pinout positions refer to the arrangement of pins on an integrated circuit. The difference between the two standards is the location of the orange and green pins. Government requires the use of the preferred TA standard for wiring done under federal contracts. The following diagrams look at the jacks from the front.

The wiring at the rear of the jack varies by manufacturer and may not be in the same sequence as the front. However, compliance with the color codes is maintained by routing the connections at the back to the proper sequence at the front of the jack. That is usually done by a small printed-circuit board in the jack assembly. Facebook Tweet LinkedIn. This was to maintain backward compatibility with older equipment like in the residential space fax machines, etc.

There is a warning in the commercial standard about making certain that both ends of the cable are terminated to the same scheme. In other words, pick one and stick with it.

So now that we have sorted out what the actual recommendations are, another common misconception is that one wiring scheme will perform better than the other. Let me put this to bed immediately: they are identical in regards to performance.

I decided to conduct a test to prove this out. The results of the tests speak for themselves. It is a wash on performance. Well, indeed there is. Where would one use that kind of thing? In most network applications, the standard straight through cabling method is required.

For example, a computer plugged into a wall panel uses the standard cable configured with either TA or TB termination. This allows the computer to communicate with other devices on the local area network. Whether talking to a network printer or mail server, the data traverses the network because all the cabling has been put together using one of the above termination standards.

The same is true for the cabling in the wall and the patch panel where they all terminate. Now for other applications, we may need to connect a computer directly to another computer or a host-to-host connection. These two computers need to use a crossover cable. Please note that the use of cross-over cables is very rare in the modern age. There are some specialized applications for them, but you will likely never see it in the wild. Summing this up, the whole TA vs TB thing has been a needless source of confusion and controversy for over two decades.

Understanding how the standards evolved and your chances of encountering a situation where you will be forced into using one scheme or the other is not likely to happen in this day and age. Just pick one and go. With that, I say…. While the information on this website is about data networking and electrical issues, it is not professional advice and any reliance on such material is at your own risk.