Network cable is an essential part of the entire network transmission medium, and plays a vital role. So do you know about network cables? What is twisted pair cable? What are STP, SFTP, UTP, FTP, and ASTP? And how to distinguish among many network cables. With these questions, in this article, we will give you a detailed answer to some basic knowledge about network cables.
What is the function of the shielded network cable?
The shielded network cable is mainly aimed at the environment with strong interference. The interference environment will cause the network cable to transmit signals intermittently or even interrupt, and the signal cannot be transmitted normally. The use of shielded network cables can well resist interference, maintain normal transmission, and have good confidentiality performance. The shielding structure of shielded wiring has inherent advantages in reducing mutual interference between cables. It can not only shield external electromagnetic signals, but also aluminum foil at the same time. The electromagnetic leakage of the cable itself is blocked, and interference signals are not transmitted to affect the work of other cables, which can prevent information from being eavesdropped.
In the shielded network cable, there will be a copper wire, that is, the ground wire. A shielded RJ45 socket can be used, and one end of the drain wire is grounded when in use. The ground wire can better shield external signals. Shielded network cables need good grounding, and shielded lines can reduce the impact of strong interference on network signals. In non-essential cases, do not use shielded network cables, because the wiring requirements of shielded network cables are high, not only the accessories in the system required to be It is shielded and must be well grounded to function. If the grounding is not good, then the effect will be very poor.
If the grounding point arrangement is incorrect, the grounding resistance is too large or the grounding potential is unbalanced, it will cause grounding noise, that is, a potential difference will be generated at a certain point of the transmission channel, so that interference current will be generated on the metal shielding layer. At this time, the shielding layer itself forms the largest source of interference. The wiring requirements for shielded network cables are relatively strict. All accessories need to have shielding performance, and a good grounding system is required. In actual construction, it is difficult to ground them all perfectly, so the shielding layer itself becomes the biggest source of interference, and the performance may even be inferior to that of the unshielded twisted pair.
What is a twisted pair cable?
Twisted pair cable: As a transmission medium, it is formed by two thin copper wires wrapped with insulating material intertwined at a certain ratio.
Why should two wires be twisted in pairs: This intertwining changes the original electronic characteristics of the cable, which can not only reduce its own crosstalk but also prevent the signals on other cables from affecting the pair of cables to the greatest extent. interference.
How to distinguish STP, SFTP, UTP, FTP, and ASTP
STP
Independently shielded twisted pair, an aluminum foil layer is added outside the core wire, each pair of wires has an aluminum foil shielding layer, the purpose is to reduce the attenuation of the signal. There is also a metal braided shielding layer for each 4-pair cable package, which has reached the structural standard of Category 7 cable. It is suitable for high-speed networks and high-confidence transmission can support future application updates, can unify the wiring platform, and transmit various media information together.
SFTP
Double-shielded twisted-pair cable, a braided mesh is added on the basis of STP’s aluminum foil, usually, aluminum-magnesium wire braided mesh, tinned copper mesh, and the outer layer is a PVC outer quilt. Generally speaking, there are two layers of shielding layers, and There must be an insulating separation between the two shields. Its advantage is that it can effectively reduce the environmental magnetic field and signal interference, and the internal signal attenuation is low. The disadvantage is that it has poor flexibility and is expensive. This kind of wire with anti-interference and highly confidential transmission is suitable for professional wiring projects in special environments.
UTP
Unshielded twisted pair cable, which is the most widely used wiring system wire in the general market at present. It is used for ordinary network applications with transmission bandwidth below 250MHz and no special performance requirements. The overall performance meets the requirements, the price is cheap, and construction and maintenance are. convenient. However, the highest performance limit of this type only supports the cabling system of six types of network cables.
FTP
Twisted pair cable shielded by aluminum foil, which has the advantages of large bandwidth, certain anti-interference ability, reduced signal attenuation, low smoke, halogen-free recovery, and environmental protection.
ASTP
The armored twisted-pair shielded network cable (cable) is a special double-shielded network cable. On the basis of the above double-shielded cable, the outer layer is a steel tape armored layer. When in use, both ends of the steel tape armored layer are used. Ground, one end of the innermost shield is grounded. In addition to the effect of double-shielded wires, it has high strength and can be used in wiring systems with frequent rodents or explosion-proof requirements. Generally, shielded wires are more expensive than unshielded wires in cost and installation, and their bending performance is slightly worse. But it is suitable for some special environments and integrated wiring of screen systems. You can make a reasonable choice after understanding your own situation, and optimizing the cost and wiring effect.
The above is all the analysis of the network cables of these structures. If you have any requirements for network cables and peripheral products, you can contact us at any time.
