Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
УДК 621.391.1 Rudnytska T. H. Teacher Veklich O.O. Topolska A. I. Students of Group 1TK-09 Vinnytsia National Technical University COMMUNICATION NETWORK CONSTRUCTIONS APPLICATION IN EDUCATIONAL PROCESS The humanity is standing at a critical point in the application of technology in order to empower and extend the global network. Nobody denies the fact that internet globalization has greatly succeeded. The global network develops simultaneously with social, commercial, personal, political interconnections. The innovators create new products and services in order to emphasize the advantages of the networks. Communication is as important to us as the reliance on water, air, food, shelter. Different methods that we use to share information are constantly evolving. Nowadays our communication is being improved and enhanced. It is unbelievable how quickly the Internet has become an integral part of our daily routine. The network is transparent to the millions of users due to the complex of interconnections of media and electronic devices. The communication begins with information that has to be sent via the media from one individual device to another. The basic communication structure consists of message source, message destination and channel. In reality some additional components are used. They are encoder, transmitter, receiver and decoder. The end devices included to the network may play the role of client, server or both client and server. They are computers, network printers, VoIP phones, security cameras and mobile handled devices. These devices perform the interface between human network and communication network. Intermediary devices connect the individual hosts to the network. Network access devices (hubs, switches, wireless access points), internetworking devices (routers), communication server and modems, security devices (firewalls) are related to intermediary devices. Network media are a special channel over which a message travels. There are some kinds of media: copper, fiber optics, wireless. The criteria according to which the media may be chosen are the size of the area covered, the number of users connected, the number of types of services available. Networks types are Local Area Network (LAN), Wide Area Network (WAN), Metropolitan Area Network (MAN) and Personal Area Network (PAN). The difference is that LAN is used for separate building or company. WAN makes the interconnection among other LANs. There are special predetermined rules that are called protocols. The protocol suite is a group of inter-related protocols. All protocols are implemented in software and hardware loaded on each host. The protocols are represented as layered hierarchy. Knowing the network construction a new question about its work appears. The typed message is converted into the binary code and sent to interface card. The interface card transports the information represented in signal form to the switch in the same network. When the message gets router interface it is sent to the other network. In the dignified network the message will be transported in the same way. One of the perspective communication channels is the satellite communication which allows broad access to the information throughout the world at any time. In satellite communication signal transferring between the sender and receiver is done with the help of satellite. In this process the signal which is basically a beam of modulated microwaves is sent towards the satellite. Then the satellite amplifies the signal and sends it back to the receiver’s antenna present on the earth’s surface. So, all the signal transferring occurs in space. Two types of satellites which are commonly used in satellite communication are active and passive satellites. Passive satellites are just plastic spheres with metal coating. They reflect the coming microwave signals coming from one part of the earth to other part. In active satellites an antenna system, transmitter, power supply and a receiver are used. These satellites are also called transponders. The signal modulated on the earth is transmitted to the transponder where this signal is amplified and stored in satellite’s memory. Then signal is transmitted back to earth when earth properly faces the satellite. Some active satellites also have programming and recording features. Satellites come in many shapes and sizes and have many uses. The first artificial satellite, called Sputnik, was launched by the Soviet Union in 1957 and was the size of a basketball. Its purpose was simply to transmit a Morse code signal repeatedly. In contrast, modern satellites can receive and transmit hundreds of signals at the same time, from simple digital data to complex television programs. They are used for many purposes such as television broadcasting, amateur radio communications, Internet communications, weather forecasting and Global Positioning Systems (GPS). Communication satellites act as relay stations in space. One could imagine them as very long, invisible poles that relay high frequency radio waves. They are used to bounce messages from one part of the world to another. The messages can be telephone calls, TV pictures or Internet connections. Certain communications satellites are, for example, used for broadcasting: they send radio and TV signals to homes. Nowadays, there are more than 100 such satellites orbiting Earth, transmitting thousands of different TV (and radio) programs all over the world. Satellite Internet access is Internet access provided through satellites. Latest satellites can achieve speeds up to 18 Mbps. Satellite Internet generally relies on three primary components: a satellite in geostationary orbit, a number of ground stations known as gateways that relay the Internet signal to and from the satellite via microwaves, and a VSAT (Very-small-aperture terminal) dish antenna with transceiver, located at the user end. Other components of a satellite Internet system include a modem that translates the signal from and back to a computer and a centralized Network operations center (NOC) for monitoring the entire system. One of the most important network applications is E-learning. In this way students may get the same diplomas as obtained in universities. Information is represented in the form of video, audio and other entertaining forms. E-learning gives the students a great opportunity to make video conferences with teachers. The lessons may be organized at any place and at any time. Thus such kind of education has many advantages. People should be aware that networks play the vital role in current communication. The humanity may only follow this constant process of communication development. Thus communication network contributes to the efficiency of the teaching process in all higher educational establishments. Література 1. «CCENT/CCNA ICND1 640-822 Official Exam Certification Guide» by Wendell Odom, 3rd Edition, DVD-ROM, 800 pages, ISBN 978-1-58720-425-8, 2012 2. «Computer Networks: Principles, Technologies and Protocols for Network Design» by Natalia Olifer, Victor Olifer, 1000 pages, ISBN 978-0-470-06407-8, September 2007, ©2005 3. Basics of satellite communications — Режим доступу до журн.: http://www.jisc.ac.uk/whatwedo/themes/network/sat/report3.aspx 4. What is Satellite Communication? — Режим доступу до журн.: http://www.thebigger.com/physics/principles-of-communication/what-is-satellitecommunication/