The wireless network uses radio frequencies, microwave to connect computer. Figure 1: Coaxial cable Wireless networks have given the flexibility to be mobile and this improves availability. This paper In early days of networks, network people focuses on different hardware requirements, the used coaxial cable as shown in figure 1 to connect range and benefits of wired and wireless networks.
Coaxial cable was one of the Finally a method is proposed to improve the common cable used for LAN. The other name for transmission limit of GiFi.
Coaxial cable are of two This paper is logically split into 6 sections. Table 1 furnishes the facts about conclusion. They are: Bandwidth 2. The cable may be used over many miles because there is no electrical EMI and the bandwidth is very high. Extra care is taken to install a fiber optic cable and it used for the backbone of a network. To locate a flaw in the fiber optic cable high end tools are needed.
The core of the cable consists of glass or plastic, and it is safeguarded by a layer of gel or Figure 2: Twisted pair cable light reflecting plastic.
A plastic insulation sheath then surrounds the entire cable. Fiber Optic Twisted-pair cable as shown in the figure transmission speed is of 10 Gigabits per second.
Each pair is Figure 3: Fiber-Optic cable twisted around each other at a different rate. Each pair has a color-coded, confining to the standards. The Repeaters are one of the networking sequence of the wires decides how the wires are devices. It is used to enhance a cabling system to terminated on the RJ connector.
Either sequence extend beyond its maximum allowed length. It does may be used to set up a network. On a network the this by amplifying the network voltages to travel same sequence is used throughout the network. The further. It is more like amplifiers and are very signal quality depends upon correctness in pairing inexpensive. The only constraint in repeaters is that of wires.
Table 3 describes about the facts of it can only be used to regenerate signals between twisted pair cable. Transmission distance Maximum distance is meters. Usage LAN www. For many of the first wireless technology. It connects devices years cables ruled the world of computer networks.
Two types of because of its higher bit rates and faster network are used: transmission. The refractive index is related to density. Therefore, a fiber of gradual index has variable density.
The density is higher in the center of the nucleus and gradually decreases to the edge. The figure shows the impact of this variable density on the propagation of light rays.
The signal introduced in the center of the nucleus. From this point, only the horizontal ray moves in a straight line through the central zone, of the constant density. Rays at other angles move through a series of densities that change constantly. Each density difference causes the beam to refract into a curve.
Singlemode The Singlemode uses staggered index fiber and a very focused light source that limits the rays to a minimal range of angles, all close to the horizontal. Monomode fiber is manufactured with a much smaller diameter than multimode fibers and with a density refractive index substantially lower density decrease results in a critical angle that is very close to 90 degrees to make the propagation of rays are almost horizontal. In this case, the propagation of the different rays is almost identical, and the delays are negligible.
All rays reach the destination together and can recombine without distorting the signal. Optical fibers define by the ratio between the diameter of their core and the diameter of their cover; both expressed in microns micrometer. The figure shows the composition of a typical fiber optic cable.
The fiber is formed by a core surrounded by a cover. In most cases, the fiber covered by an intermediate level that protects it from communication.
Finally, the entire cable enclosed by an outer casing. Both the core and the cover can make of glass or plastic, but they must be of different densities.
Also, the inner core must be ultra-pure and completely regular in shape and size. The chemical differences of the material and even small variations in the size and shape of the channel alter the angle of reflection and distort the signal. Some applications may admit some distortion, and their cables may be cheaper, but others depend on complete uniformity.
The outer covering or sheath can make with various materials, including a coating of Teflon, plastic, fibrous plastic, metal pipe, and metal mesh. Each of these materials serves a different purpose. Plastics are light and cheap but do not provide structural strength and can emit smoke when burned. Metal tubing provides greater strength but increases costs. Teflon is lightweight and can use outdoors, but it is expensive and does not increase the robustness of the cable.
The choice of material depends on where the cable installed. As we have seen, the objective of the fiber optic cable is to contain and direct rays of light from the source to the destination. For transmission, the emitting device must equip with a light source and the receiving device with a photosensitive cell called a photodiode capable of translating the received light into the current that can use in a computer. LEDs are the cheapest source, but they provide an unfocused light that starts at the ends of the channel with uncontrolled angles and fades with distance.
For this reason, the use of LEDs limited to short distances. The connectors for the fiber optic cable must be as accurate as of the cable itself. With metal means, the connections do not need to be as accurate as long as both conductors are in physical contact. On the other hand, with the optical fiber, any misalignment with either another segment of the core or with photodiode results in the signal reflected the emitter, and any difference in the size of the two connected channels results in a change in the angle of the signal.
Also, the connections must complete even if the connected fibers not wholly joined. An interval between both cores results in a dissipated signal; A tightly pressed connection can compress both cores and alter the angle of reflection.
With these restrictions in mind, manufacturers have developed several connectors that are precise and easy to use. All popular connectors are barrel-shaped and connectors in male and female versions. The cable equipped with a male connector that is blocked or connected to a female connector associated with the device to be connected.
The main advantage offered by the fiber optic cable over the twisted pairs and the coaxial cable is Immunity to noise, less attenuation of the signal and higher bandwidth. Immunity to noise : Because transmissions use light instead of electricity, noise is not essential. The external light, the only possible interference, is blocked by the opaque coating of the channel. Less attenuation of the signal : The transmission distance of the optical fiber is significantly higher than that achieved in other guided media.
A signal can be transmitted over miles without the need for regeneration. Higher bandwidth : The fiber optic cable can provide bandwidths and thus data rates substantially more significant than any twisted pair or coaxial cable.
Currently, data rates and the use of bandwidth in fiber optic cables not limited by the medium, but the available technology of generation and reception of the signal. The main disadvantages of fiber optics are cost, installation, maintenance, and fragility. Cost : The fiber optic cable is expensive. Because any impure or imperfection of the nucleus can interrupt the signal, the fabrication must be laboriously precise. Equally, getting a laser light source can cost thousands of dollars, compared to the hundreds of dollars needed for electric signal generators.
Installation of the twisted pair cable is easy, and it is a lightweight cable. The frequency range for twisted pair cable is from 0 to 3. The degree of reduction in noise interference is determined by the number of turns per foot. Increasing the number of turns per foot decreases noise interference. An unshielded twisted pair is widely used in telecommunication. Following are the categories of the unshielded twisted pair cable:.
A shielded twisted pair is a cable that contains the mesh surrounding the wire that allows the higher transmission rate. JavaTpoint offers too many high quality services. Mail us on [email protected] , to get more information about given services. Please mail your requirement at [email protected] Duration: 1 week to 2 week. Computer Network. Transport Layer Transport Layer Protocols. Next Topic UnGuided Media. Reinforcement Learning. R Programming. React Native. Python Design Patterns.
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