Telecommunications channels using a variety of telecommunications media. This includes cable, pairs, double angle cable, and fiber optic cables, which are physically connecting devices on the network. Also includes short wave terrestrial (terrestrial microwave), satellite communication systems, cellular phones, as well as LAN and packet radio, which are used, microwaves and other radio waves. In addition, there is also an infrared system, which uses infrared light to send and receive data.
Public telephone cable, which consists of copper wires, twisted pairs (cable pair), is a telecommunications media the most widely used. These cables are used for communications networks around the world, in various forms, and is widely used in home phone systems, and office, as well as in many LAN and WAN. Speed transmission, between 2 million bytes per second (the guards) to 100 million bytes per second (with protection).
Coaxial cable consists of copper-aluminum wires datau, powerful and packed with a barrier, which serves as an insulator and protector. Penutupkabel insulation and minimize interference, the signals carried by the cable. Group of coaxial cable, the cable can be united in order to be easily installed. This high-quality paths, can be placed in the basement, or in the bottom of lakes, and oceans. Coaxial cable enabling, high speed data transmission, (from 200 million to 500 million bytes per second - 200 MBps to 500 MBps). And more widely used than the cable pairs, in a metropolitan area, for cable TV systems, and for computer connection, a short distance, and peripheral equipment. Coaxial cables are also used in many office buildings and other workplaces to the LAN.
Fiber Optic Cables.
Fiber optic cables are composed of one or more hair-thin filament, fiber glass wrapped with a protective jacket. Optical fibers, can produce a glowing pulse elemn (photons) produced by the laser beam, with a transmission rate of up to trillions of bytes per second (Terabyte per second or Tbps). This, about a hundred times larger than coaxial cable, and a thousand times better than cable pairs. Fiber optic cables provide substantial unkuran, and weight reduction, as well as increasing the speed and capacity, greater. Optical fiber cable diameter half inhi, can carry more than 500,000 channels, compared with only about 5,500 channels on a standard coaxial cable.
Fiber optic cables are not affected or mengasilkan electromagnetic radiation, therefore, the optical fiber can be placed on the same cable. Fiber optic cables do not need to pengulanagn signal transmission, unlike copper cable media,. Fiber optics also has a data error rate lower than other media, and more difficult to be tapped, rather than electrical wires. Optical fiber cables, have been installed in different parts of the world, and is expected to replace other communication media in many applications.
The new optical technologies such as dense wave division multiplex (dense wave multiplexing, DWDM), can share a glass fiber to 40 channels, allowing each piece to address the 5 million calls. DWDM technology in the future is expected to be 1.000 mebagi each fiber channel, so each strand, can handle 122 million calls. In addition, a newly developed optical router will send the optical signal, 2.500 miles without needing retransmission, thus eliminating the need for repetition every 370 miles to produce a return signal.