Wiring certification and Testing

Wiring of the construction process quality can not completely determine the entire network cabling quality, so the wiring must be certified testing to determine whether the link can meet the design requirements. Wiring certification, for today is important, for tomorrow is a matter of Life-and-death.
In many cases, Class 5 network cabling is used to support 10Mbps Ethernet. This kind of network is able to run well in 3 kinds of wiring, the performance of 5 type cable wiring is far from reflected. The future high-speed network needs to support 100M bps 5 class cabling performance, how to ensure that today's wiring can support the future of high-speed network?
TIA/EIA-568A's TSB-67 as a field test specification for UTP Cabling Performance was formally adopted in the autumn of 1995, which comprehensively defines the field test contents, methods and requirements for the test equipment for cabling. The ISO/IEC 11801 standard was also formally passed last July, and it also set a corresponding standard for the testing of network cabling.
TSB-67 first defines two test patterns, Basic link and channel. The biggest difference between the two is that basic link does not include cables that are used by the client (which includes connecting the user's PC with an information outlet or wiring rack to the hub), while channel is defined as a complete end-to-end link, it includes all links to network sites and hubs, The user's end cable must be part of the link and must be connected to the tester.
The cabling company may want to present a report to the user with basic link, and the user may want a channel report. No matter which report is to prove that the wiring can pass the 5 class requirements, but the scope and definition of the test is not the same, Basic link does not include the user-side cable defined in channel, so it should be strict, so that for the entire link or channel. What test mode to choose in the test must be carried out according to the user's actual needs. ---http://bianceng.cn (computer science)
We take a 5 class wiring test report as an example, a brief description of the wiring of the certification at least what content:
(Note: The sample is used fluke Company's digital cable tester DSP-100 using TIA 5 class channel method test)
The necessary test parameters are specified in the TSB-67: Wiring diagram, length, attenuation, near-end crosstalk (bidirectional).
Although the necessary test parameters in TSB-67 only define these four items, but the other parameters of cabling can be shown in these four parameters, the wiring of the field test report should be more concise, so the use of testing equipment can be measured how many parameters is not important.
The most common factor that affects cable performance is near-end Crosstalk next. Near-end crosstalk occurs when two pairs of adjacent lines generate false signals from each other on the electric field. In short, near-end crosstalk is a signal leak from one pair of lines to another.
External signal disturbances generally come from lighting (especially fluorescent lamps), motors, machinery, radios, and other sources of interference. The signals transmitted in the cable are disturbed by these external signals, and the negative effect of next and external signals increases as the network signal travels faster. Therefore, in order to support high-speed local area network, users should use 5 types of UTP and cable wiring, and cabling design to consider the trend of the wiring.
Attenuation is the signal in the transmission of energy loss along the cable, wiring design to specify from the wiring between the maximum length of the workstation cable (Basic Link 94m, Channel 100m).
The circuit's obstruction to the current is called the characteristic impedance, which is measured in ohms. The characteristic impedance of the cable must be matched with other network devices and cable-connected parts.
These electrical characteristics of the cable failure generally will not cause the entire network crashes, but will weaken the signal transmission, resulting in loss of data or network performance degradation. In the test, a typical link can be selected to measure its attenuation and the frequency of the near-end crosstalk of the characteristics of the graph for reference.
If a cabling system passes the test required by TSB-67, we can be assured that no matter what particular network and application the cabling system will be used for in the future, it will be able to provide 100Mbps.