Communication Technology By Bhupendra Ratha, Lecturer School of Library and Information Science Devi Ahilya University, Indore Email: [email protected] What is the Communication? A word communication has been drives from the Latin word “Communicare” which means to communicate, the word used for exchange the information. Communication needs languages as the channel for communication between two or more than two person. Basic requirements and Process of a good communication Language Sender Message Receiver Channel Channels of communications Body language Oral communication Verbal communication Audio-visual communication Mass communication Tele-communication Wireless communication Types of communications One to one communication Centralized communication Circular communication Free flow communication One to One Hy, Raj How are you Fine, I hope you also fine Centralized communication Circular communication Free-Flow communication Communication Technology Use the modern technology for communicate the information by different channels and medias are called communication technology such as electronic telegraph, telephone, radio, TV, computer, wireless and networking etc. Tele-communication Tele-communication is the part of Information and Communication Technology because in the very short time we can get information at the international level. It is the process of exchange the information to long-distance Characteristics of Tele-communication Any one can use the Tele-communication technology for exchange the information. The message may be send in coding language which understand only sender and receiver. Information are easily exchange in the different format such as text, numerical, graphical, audio-visual etc. Cont… It can exchange information globally or each and every area of the world. Save the time, money and human power. It make the privacy of message. History of Tele-communication 3000 BC Smoke signals, Drums, Pigeon etc. 490 BC Heliographs 1837 AD Telegraph by Samuals F B Morse 1876 AD Telephone by Allexander Grahmbell Cont… 1894 AD Radio by Marconi 1926 AD T. V. by J. L. Baird 1963 AD Audio tape by Phillips com. 1969 AD Internet by ARPANET Cont… 1977 Fiber optical telephone cable. 1980 1981 Walkman by Sony comp. 1990 WWW by Terner Lee html Tele-communication media Bounded/Cable media Boundless/Wireless Media Coaxial Cable Radio Wave Twisted-Pair Cable Microwave Fiber-Optical Cable Satellite Bounded/Cable Media When connect the telecommunication component with the cable and exchange the information they call bounded/cable media. There are three types of cable media very commonly used and they are; 1. Coaxial Cable 2. Twisted-Pair Cable 3. Fiber-Optic Cable Coaxial Cable Coaxial cable gets its name because two conductors share a common axis; the cable is most frequently referred to “coax”. A type of coaxial cable that we may be familiar with is our television cable. Its components are as follows; A center conductor An outer conductor An insulation layer A plastic encasement (Jacket) A Center conductor A center conductor, although usually solid copper wire is sometimes made of standard wire. A outer conductor A outer conductor forms a tube surrounding the center conductor. This conductor can consist of braided wires, metallic foil or both. The outer conductor, frequently called the shield, serves as a ground and also protects the inner conductor from EMI. An insulation layer An insulation layer keeps the outer conductor space evenly from the center conductor. A plastic encasement (Jacket) A plastic encasement protects the cable from damage. Classification of Coaxial Cable Thinnet :- 0.25 inch (6mm) 610 feet Thicknet :- 0.50 inch (13mm) 1650 feet Twisted-Pair Cable Twisted pair cable is popular very much because of its inexpensiveness and ease of installation. A basic twisted pair cable consists of two strands of copper wire twisted together. The twisting reduces the tendency of the cable to radiate radio frequency noise that interferes with nearby cables and electronic components, because the radiated signals from the twisted wires tend to cancel each other out. Classification of TPC Shielded Twisted-Pair Cable (STPC) Unshielded Twisted-Pair Cable (UTPC) Shielded Twisted-Pair Cable (STPC) Shielded Twisted-Pair Cabling consists of one or more twisted-pair of cables enclosed in a foil wrap and woven copper shielding. Early LAN designer used STPC because the shield performed double duty, reducing the tendancy of the cable to radiate EMI and reducing the cables sensitivity to outside interference Unshielded Twisted-Pair Cable (UTPC) UTPC doesn’t incorporate a braided shield into its structure. However characteristics of UTPC are similar in many ways to STPC, differing primarily in EMI. Fiber-Optical Cable The center conductor of a fiber-optic cable is a fiber that consist of highly refined glass or plastic designed to transmit light signals with little loss. A glass core supports a longer cabling distance, but a plastic core is typically easier to work with. The fiber is coated with a cladding that reflects signals back into the fiber to reduce signal loss. A plastic sheath protects the fiber. Cont… Fiber optic network cable consist of two strands separately enclosed in plastic sheaths. One strands sends and the other receivers. Two types of cable configurations are available; 1. Loose configurations. 2. Light configurations. Loose configurations Loose configurations incorporate a space between the fiber and the plastic encasement, this space is filled with a gel or other material. Tight Configurations Tight configurations contain strength wires between the conductor and the outer plastic encasement. Comparison of cable media Cable type Cost Installation Less than TPC Inexpensive / easy 10 mbps 500 m Twisted Pair Lowest Fairly easy 100 mbps 100 m Highest Expensive / Difficult 100mbps to above 10 km Coaxial Fiber-Optic Capacity Range Boundless/Wireless Media When the information transmission without cable media they are called boundless/wireless media. There are many types of wireless media ; 1. Radio wave 2. Microwave 3. Satellite Radio wave In radio transmission a radiating antenna is used to convert a time-varying electric current into an electromagnetic wave, which freely propagates through a no conducting medium such as air or space. In a broadcast radio channel, an omnidirectional antenna radiates a transmitted signal over a wide service area. Microwave Microwave is the most important media of telecommunications. The transmission path of microwave links can be established between two land-based antennas or tower. Satellite In 1954 the satellite technique has established. It is also most important media of telecommunication. Easily and authentic data transmission by this media. Most telecommunication satellite have been placed in Geostationary Orbit (GEO), a circular orbit 35,785 km above the earth. Modes of Telecommunications Serial and parallel Simplex, Half duplex and full duplex Modulation-demodulation Radio wave Microwave Satellite wave Serial and parallel In serial communication, only one bit transmitted at a time and it is the suited for slow and long distance communication, whereas in parallel transmission group of bits as transmitted at a time, which is suited for high speed and short distance communication. Simplex, Half duplex, Full duplex Television Simplex Half duplex Or Computer Full duplex and Computer Modulation-demodulation Analog Input A/D Converter (Modulation) Digital Signals Digital Input Signals D/A Converter (Demodulation) Digital Input Signals Analog Output Mode of Radio wave communication Electronic signal Master Station Electromagnetic signals Mode of Microwave communication Transmitter Repeater Receiver Output signals Input signals Atmospheric signals (Air and Surface) Master Station Mode of Satellite Wave Communication Output signals Satellite Input signals Master Station Master Station Component of Telecommunication 1. 2. 3. 4. 5. The basic components are follows; Sender/Transmitter Message Language Media Receiver Other Component of Telecommunication Modem Repeater Hub Bridge Router Switch Brouter Gateway Modem MODEM is contraction of Modulator/ Demodulator, which allows a computer to transmit the information over a telephone line to another computer. The modem converts the digital signals into analog signals and analog signals to digital signals. Repeater A networking component that extends a network by boosting the signal so that it can travel farther along the cabling. A repeater is a form of digital amplifier that works at the physical layer of OSI mode for regenerate of signals. Hub Hub is also called wiring concentrators, provide a central attachment point for network cabling. Hubs can be divided in three categories; 1. Passive Hub 2. Active Hub 3. Intelligent Hub Bridge A network component used either to extend or to segment networks. Bridges work at the OSI data link layer. They can be used both to join dissimilar media. Bridges come in three basic types; 1. Local bridges 2. Remote bridges 3. Wireless bridges Router Router works at the network layer of OSI model for networking to move packets between using their logical addresses are the destination host. Switch Bridge with more efficiency is called switch. A switch may act as a multi-bridge to connect devices in a LAN. Switch has a buffer for each link to which it is connected. Brouter Any network device having the capabilities of both a bridge and a router. Usually, a brouter will act as a router for one protocol and a bridge for all other protocols. Brouters are not common in network. Gateway Gateway is used to connect the different protocol based networks (like TCP/IP, Apple Talk etc,) A term for a broad category of network components that allow communication between different networking architectures and different protocols. Gateways generally operate at the higher levels of the Open Systems Interconnection.