Short link problem of wiring problem

When you perform a test on a cabling system, you are actually testing the system with a series of test parameters. These parameters determine whether the test system meets the performance requirements of the corresponding category, which is the standard specification defined by TIA, including PS ACR, Psnext, Psfext, attenuation, and so on. The echo loss is one of the parameters, which refers to the ratio of the signal reflected back on the transmitter to the original signal sent.
　　
The importance of ECHO loss
Class 6 Tests are tests that verify the system's use in a Full-duplex transmission environment or Gigabit Ethernet applications. Echo loss is an important parameter that may cause errors in such networks. Because a Full-duplex network can send and receive information at the same time, even though it does not receive any signals, large reflection signals may be viewed as receiving signals, and this effect can generate error codes. Therefore, the return loss is a rigorous parameter in the Class 6 test, and it is a parameter that is not easy to pass the test.
　　
Short link problem
The main cause of the return loss is the impedance mismatch between the cable and the end-socket contact Pins. It is impossible to completely eliminate this situation because there is no possible 100% match in the world. At the same time, the short cable length increases the loss effect because there is not enough cable to attenuate the echo signal. For relatively long cables, the probability of receiving an echo signal on one side of the transmitter is higher.
　　
Recently, "Short link" This situation in the 6-class cabling system has become very common application. As in IDC, it brings more difficulties to application engineers and cabling installers. According to the Tia/eia standard, "Short link" is defined as a horizontal cable link between connectors less than or equal to 15 m. The short link problem is defined as the next and return loss effects of the second connector are not completely attenuated when the horizontal cable distance between the two connectors is sufficiently shorter than the standard. Tia/eia indicates that the distance is less than 15 meters. (Computer science)
　　
Short Link Solutions
This is an important guideline to keep in mind, because other factors may have reduced the link anti interference margin, such as the end-connection technology and cable management methods poor factors. In general, longer cable lengths reduce these negative effects due to the larger attenuation of the cable itself. However, shorter cable lengths, or short links, do not reduce these effects. In addition, the 6-class link to the allowable specification margin is generally lower than the 5-type link, so its error tolerance for less, more stringent requirements.
　　
In general, it is recommended that designers avoid the use of short links in class 6 cabling systems to maintain the maximum net free amount of parameters. One way to achieve this is to allow the "loose margin" cable to go, that is, to take more long-distance cables, so that each line cable length more than 15 meters.