Fiber optic cable, twisted pair, cable difference

In the network hardware, there is a category that can not be ignored is the network transmission medium, we usually called the network cable. At present, the more common network cable is fine twisted pair, fiber optic cable, coaxial cable, and coarse coaxial cable. 1. Fiber-optic cable Fiber-optic cable is a new generation of transmission media. Compared with copper media, the fiber has greatly improved in terms of security, reliability, and network performance. In addition, the bandwidth of optical fiber transmission exceeds that of copper cables, and the maximum connection distance it supports is more than two kilometers. This is an inevitable choice for building larger networks. Because fiber optic cable has the advantages of good anti-electromagnetic interference, strong confidentiality, high speed, and large transmission capacity, its price is also relatively expensive, and it is rarely used in home use. At present, there are two different kinds of optical fibers, which are single-mode optical fibers and multi-mode optical fibers (the so-called “mode” refers to a beam of light that enters the optical fiber at a certain angle). Multimode fibers are generally used for network connections in the same office building or in relatively close areas. While single-mode fiber delivers higher quality data and longer transmission distances, it is often used to connect office buildings or geographically dispersed networks. If optical fiber cables are used as the network transmission medium, devices such as optical transceivers must be added. Therefore, the cost is greater and it is less commonly used. 2. Twisted Pair Twisted Pair is a flexible communications cable that contains pairs of insulated copper wires. It is characterized by its low cost and is therefore widely used, such as our common telephone lines. According to the maximum transmission rate, twisted pair can be divided into 3 categories, 5 categories and 5 categories. The rate of Category 3 twisted pairs is 10 mb/s, Category 5 up to 100 mb/s, and Super Category 5 up to 155 mb/s or more, which is suitable for future multimedia data transmission requirements. Therefore, it is recommended to use 5 types or even 5 types of doubles. Stranded wire. Twisted pair can also be divided into shielded twisted pair (stp) and unshielded twisted pair (utp). Although the stp twisted pair has a low speed (only 4mb/s), it is much more resistant to interference than the utp twisted pair, so the price is much more expensive, and now these twisted pairs are a few dollars a meter cheaper than expensive. More than ten dollars can buy one meter. In contrast, utp twisted pair prices are generally around one meter one yuan, which is relatively low. In addition, popular 10m and 100m unshielded twisted pair are popularly known as 10base-t and 100base-t, which are often seen in the market. The rj45 crystal head is also used for the twisted pair cable. It is used to make the joint between the twisted-pair cable and the NIC of the network card. The quality of the cable is directly related to the stability of the entire network and cannot be ignored.

3. Coaxial cable coaxial cable is a kind of transmission medium which many friends are familiar with. It is a cable with a central copper conductor wrapped by a layer of insulated wire. Its greatest feature is its good anti-interference ability and stable transmission data. The price is also cheap, so it was once widely used, such as closed-circuit television lines. However, more coaxial cables were used in the past, mainly because the cost of the bus structure network composed of coaxial cables is lower, but the damage of a single cable may cause the entire network to collapse and maintenance is difficult, which is its biggest drawback. Coaxial cables used in Ethernet applications are mainly classified into coarse coaxial cables (10base5) and fine coaxial cables (10base2). Rough coaxial cables are not used much now, and there are still some markets for fine coaxial cables. Fine coaxial cable market price of a few yuan a meter in general, is not too expensive. In addition, the coaxial cable is used to connect with the bnc head. The coaxial cable sold on the market is generally a finished product that has been connected with the bnc head.