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Information and Communication Technologies and Development. Dr. Kate Litondo Mobile: 0733 223 635. LECTURE ONE. INTRODUCTION TO INFORMATION AND COMMUNICATION TECHNOLOGIES FOR DEVELOPMENT (ICT4D). What is ICT?. Umbrella Term for communication devices and applications such as:
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Information and Communication Technologies and Development Dr. Kate Litondo Mobile: 0733 223 635
LECTURE ONE • INTRODUCTION TO INFORMATION AND COMMUNICATION TECHNOLOGIES FOR DEVELOPMENT (ICT4D)
What is ICT? Umbrella Term for communication devices and applications such as: - Print Media -Radio - Television - Cellular Phone - Computer Hardware - Computer Software - Satellite systems It encompasses both traditional and Newer Technologies
Technological Convergence Convergence refers to previous separate technologies such as voice (and telephony features), data (and productivity application) and video that now share resources and interact with each other creating efficiencies. Computer networks are included in convergence where many different operating systems are able to communicate via different protocols (rules).
Problems with convergence A single device addressing a wide spectrum of consumer needs, breakdowns and problems become more likely. The greater the degree of converging the more vulnerable the consumer (e.g. DVD in DVD player versus DVD in computer).
ICTs Cont... Since technology has evolved in the past ten years or so, companies are beginning to converge technologies to create demand for new products e.g. 3g mobile phones that television converged movies and radio. Mobile phone are now being manufactured not only for voice and short message services (SMS) but to also hold images, video, music, television, multimedia of all types e.t.c.
ICTs Cont... Manufacturers are now integrating (video recording, data storage, security e.t.c. in one device. In the 1960s and 1970s, the development of computers and networks established the context for new meanings. Government agencies and businesses begun using computers to store and retrieve information.
ICTs Cont... Then they begun transferring this digital contents over telecommunication systems. In the mid 1970s came the realization that once information can be stored digitally and communicated across a network, the technologies that the consumers use to access information and entertainment could be transformed.
ICTs Cont… All content stored digitally could be delivered over a network and accessed through electronic devices. Consumption - other than the computer, most consumers do not use digital display devices to view information or entertainment.
Nature of Information Telecommunication provides a transport mechanism for information. Therefore, it is necessary to have basic knowledge on the subject of information for one to understand telecommunication.
Nature of Information ……… Information comes in the form of spoken words (voice), image, computer data, video or written and printed documents. Information can be sent in its original/native form from the source to its destination (receiver), information is sent in the form of signals over a transmission medium. A block diagram below might help us visualize this.
Communication System ….. The source (e.g. voice, data, video, etc.) is the origin of the information. The destination (receiver) (e.g. radio, television, facsimile, computer, etc.) is the end or the terminal of the transmission of the information. Bearing in mind what we have just discussed, we can now define telecommunication as the process of transporting or passing information from source to destination over some distances.
Communication System ….. A number of intermediate devices are involved in this transfer of information (e.g. modems, switches and so on). Some of these devices will be covered later in the lecture. There is a wide variety of signals and media.
Examples of media Physical media includes; copper wire (e.g. twisted pair or co-axial cable), glass or plastic. (E.g. fiber optic cable). Wireless media includes; radio, infrared light, space or airwaves (e.g. microwaves, satellite and cellular). The signals take the form of a voltage varying with time.
Examples of media ……. Many signals are in non-electric form (e.g. voice) when they start off. Transducers (e.g. microphone) change non-electric signals to electrical Signals. These electrical signals contain information that is to be transmitted / sent.
Examples of media ……. For any communication system to be useful, three main parts are essential. These parts are shown below:
Examples of media ……. Speech is the simplest communication man uses, yet it contains all three main parts. When a person speaks (message generation or sending end), his thoughts are converted to movement which operate vocal cords. The thoughts are in turn converted to pressure variations in the air.
Examples of media ……. These variations travel outwards (as a signal) through air (transmission channel) and they end up reaching the listener (receiving end). A more generalized view of a communication system is shown below. The elements will be discussed later in this lecture.
Elements of a Communication System …….. The urgent need to send information quickly over long distances led to telecommunications. With communication technology and systems that are in place today, communication over long distances is no longer a problem. People can communicate instantly in time using modern telephone networks.
Elements of a Communication System …….. These telecommunication networks have made it possible for people to communicate among themselves and when appropriately modified they can facilitate communication between people and electronic machines (e.g. computers or mobile phones).
Elements of a Communication System …….. • The words "tele", "phon", and "graph" are derived from Greek. • Tele – means ‘at a distance’ • Phon – means sound or speech • Graph - means writing or drawing
Elements of a Communication System …….. Therefore, telecommunication means communication at a distance. This can be done through wires called transmission lines or through atmosphere by a radio link. Other examples include:
Elements of a Communication System …….. • Telephone – speaking at a distance Television – seeing at a distance Telegraph – writing at a distance • Complex telephone networks are built using a lot of devices and methods, some of which will be discussed later in this lecture. • .
Information Systems • An information system (IS) is an arrangement of people, data, processes, and information technology that interact to collect, process, store, and provide as output the information needed to support an organization.
Information Technology • Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks).
Information and Communication Technologies • ICTs stands for "Information and Communication Technologies." ICT refers to technologies that provide access to information through telecommunications. It is similar to Information Technology (IT), but focuses primarily on communication technologies. This includes the Internet, wireless networks, cell phones, and other communication media.
Information and Communication Technologies cont… • In the past few decades, information and communication technologies have provided society with a vast array of new communication capabilities. For example, people can communicate in real-time with others in different countries using technologies such as instant messaging, voice over IP (VoIP), and video-conferencing. Social networking websites like Face book allow users from all over the world to remain in contact and communicate on a regular basis.
Information and Communication Technologies cont… • Modern information and communication technologies have created a "global village," in which people can communicate with others across the world as if they were living next door. For this reason, ICT is often studied in the context of how modern communication technologies affect society.
Information and Communication Technologies cont… • ICTs is about facilitating communication which can enable people, of whatever race, age or gender, to participate as citizens in decision making and can empower people as they shop, vote and seek expert help ‘on line’ in all areas of policy.
Information and Communication Technologies cont… • This technology can assist us to overcome some of the barriers already noted between conventional policy areas such as housing, health and social services, education and work, in order to create ‘seamless’ services.
Communication and Collaboration Systems A communications and collaboration system is an information system in an organization that utilizes ICTs to enable more effective communications between workers, partners, customers, and suppliers to enhance their ability to collaborate.
Communication and Collaboration Systems …….. Examples of Applications • Instant communication to board members • Online access to important documents • One can track deadlines, on-going projects • Document views of each member • Create a virtual boardroom by discussing online
Office Automation System An office automation system is an information system that utilizes ICTs to support the wide range of business office activities that provide for improved work flow between workers. For example: Automation of order entry, invoicing, purchasing
Office Automation System …… It is an integration of word-processing, data processing, graphics, desktop publishing etc. The backbone is • Data transmission • Mail transmission • Voice transmission
Communications Channels • Communications channels as explained before are the means by which data are transmitted from one device in a network to another. A communications channel is the path, the physical medium over which information travels in a telecommunications system from its source to its destination.
Communications Channels ….. (Channels are also called links, lines, or media.) • The channels differ in terms of capacities, the total amount of information that can be transmitted through any tele-communications channel and which is measured in bits per second (BPS).
Communications Channels …. • The channels that can be used include the following: • Wired Communications Channels: Three types of wired channels are twisted-pairwire (conventional telephone lines), coaxial cable, and fiber-optic cable.
Communications Channels …. • Twisted-pair wire: Twisted-pair wireconsists of two strands of insulated copper wire, twisted around each other. This twisted-pair configuration somewhat reduces interference from electrical fields.Twisted-pair is relatively slow. Moreover, it does not protect well against electrical interference.
Communications Channels …. • However, because so much of the world is already served by twisted-pair wire, it will no doubt be used for years to come, both for voice messages and for modem-transmitted computer data.
Communications Channels …. • Coaxial cable: Coaxial cable,commonly called "coax," consists of insulated copper wire wrapped in a solid or braided metal shield, then in an external cover.Coax is widely used for cable television. Thanks to the extra insulation, coaxial cable is much better than twisted-pair wiring at resisting noise.
COAXIAL CABLE A: outer plastic sheathB: woven copper shieldC: inner dielectric insulatorD: copper core
Communications Channels …. Moreover, it can carry voice and data at a faster rate. Often many coaxial cables will be bundled together. • Fiber-optic cable: A fiber-optic cableconsists of dozens or hundreds of thin strands of glass or plastic that transmits pulsating beams of light rather than electricity.
Communications Channels …. Unlike electrical signals, light pulses are not affected by random electromagnetic interference in the environment. Thus, they have much lower error rates than normal telephone wire and cable. In addition, fiber-optic cable is lighter and more durable than twisted-pair and coax cable.
Communications Channels …. Fiber-optic cables cannot easily be wiretapped, so transmissions are more secure. They also have greater capacity as light travels faster than electricity.
Communications Channels …. • Wireless Communications Channels: Four types of wireless channels are: Infrared transmission, broadcast radio, microwave radio, and communications satellite. • Infrared transmission: Infrared wireless transmissionsends data signals using infrared-light waves.
Communications Channels …. • The drawbacks are that line-of-sight communication is required there must be an unobstructed view between transmitter and receiver and transmission is confined to short range, e.g. Remote.