1 information technology telecommunications and networks
TRANSCRIPT
![Page 1: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/1.jpg)
1
Information Technology
Telecommunications and Networks
![Page 2: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/2.jpg)
2
Learning Objectives
When you finish this chapter, you will: Recognize why successful managers must be
familiar with telecommunications concepts and terminology.
Know the principles of communication within a computer system and among computers.
Be able to identify the major media and devices that are used in telecommunications.
![Page 3: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/3.jpg)
3
Learning Objectives
Be able to list and explain the functions of different network layouts and the concept of protocols.
Understand how telecommunications can improve operations in organizations.
Know the latest developments in telecommunications media and transmission speeds.
![Page 4: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/4.jpg)
4
Telecommunications in Business Telecommunications
Transmittal of data from one computer to another over a distance
Telecommunications has improved business in three main ways: Better communication Higher efficiency Better distribution of data
![Page 5: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/5.jpg)
5
What is Data Communications?
Data Communications Any transfer of data within a computer,
between a computer and another device, or between two computers
Two Basic Modes Parallel transmission Serial transmission
![Page 6: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/6.jpg)
6
Communication Direction
Three Modes of Communication Between Devices Simplex
One-way in one direction Half-Duplex
One-way in two directions Full-Duplex
Two-way in two directions
![Page 7: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/7.jpg)
7
Communication Direction
Figure 6.2 Simplex, half-duplex, and full-duplex communication
![Page 8: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/8.jpg)
8
Communication Direction
Asynchronous Communication In asynchronous transmission, the devices are not
synchronized by any timing aids. Advantage of asynchronous transmission
Does not need sophisticated and expensive timing hardware
Disadvantage of asynchronous transmission Overhead, time spent transmitting bits that are not a part
of the primary data
![Page 9: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/9.jpg)
9
Communication Modes
Synchronous Communication In synchronous communication, data are
transmitted using timing devices. Messages are transmitted in packets. Advantage of synchronous communication
Overhead in synchronous communication is significantly smaller than in asynchronous communication.
![Page 10: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/10.jpg)
10
Communication Modes
Figure 6.4 Synchronous transmission
![Page 11: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/11.jpg)
11
Channels and Media
Communication Channel Physical medium through which data can
be communicated. Channel Capacity
Narrow band Broadband
![Page 12: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/12.jpg)
12
Channels and Media
Figure 6.5 Transmission speed measurement unit
![Page 13: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/13.jpg)
13
Channels and Media
Media A medium is any means by which data can be
transmitted. Transmission speed
A medium’s capacity is determined by the range of bits per second at which it can operate.
![Page 14: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/14.jpg)
14
Channels and Media
Figure 6.6 Telecommunications transmission speeds of different media
![Page 15: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/15.jpg)
15
Channels and Media
Twisted Pair Telephone line made of a pair of copper wires twisted to
reduce electromagnetic interference (EMI) Coaxial Cable
Commonly used for cable television transmission More expensive than twisted pair Greater transmission rate than twisted pair Much less susceptible to EMI
![Page 16: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/16.jpg)
16
Channels and Media
Microwaves High-frequency, short radio-frequency (RF) waves
Terrestrial microwave Satellite microwave
Optical Fiber Fiber-optic technology uses light instead of
electricity to transmit data.
![Page 17: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/17.jpg)
17
Channels and Media
Figure 6.7 Characteristics of channel media
![Page 18: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/18.jpg)
18
Analog vs. Digital
Analog signals A continuous series of waves
Digital signals A series of discrete bits
![Page 19: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/19.jpg)
19
Modulation
Modification of a digital signal into an analog signal
Demodulation Modification of an analog signal into a
digital signal
![Page 20: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/20.jpg)
20
Modulation
Figure 6.8 Signal modulation
![Page 21: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/21.jpg)
21
Modulation
Amplitude Modulation (AM)
Frequency Modulation (FM)
Phase Modulation
![Page 22: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/22.jpg)
22
Modulation
Modems Devices that modulate and demodulate
signals Multiplexers
Devices that allow several telephones or computers to transmit data through a single line Frequency division multiplexing Time-division multiplexing
![Page 23: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/23.jpg)
23
Modulation
Figure 6.9 Multiplexing
![Page 24: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/24.jpg)
24
Modulation
Figure 6.10 Frequency division
![Page 25: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/25.jpg)
25
Networks
LANs (Local Area Networks) Networks within a building, or within a group of
adjacent buildings WANs (Wide Area Networks)
Networks that cross organizational boundaries or reach outside the company Value-added networks (VANs) Wireless communication
![Page 26: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/26.jpg)
26
Networks
Figure 6.11 Where wireless LANs are a good choice
![Page 27: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/27.jpg)
27
Networks
Network Topology Physical layout of the nodes in a network
Star Ring Bus Tree
![Page 28: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/28.jpg)
28
Network Topology
Figure 6.12 Network topologies
![Page 29: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/29.jpg)
29
Protocols
Communication protocols Rules governing the communication between
computers or between computers and other computer-related devices
Network protocols Rules governing a network of devices
![Page 30: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/30.jpg)
30
Protocols
Figure 6.13 Some communications software allows a user to establish protocols: bit rate, parity, number of data bits, stop bits, and a
handshake procedure.
![Page 31: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/31.jpg)
31
Protocols
LAN Protocols Polling Contention Token passing
WAN Protocols OSI (Open Systems Interconnection)
Standard protocol model Seven layers
![Page 32: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/32.jpg)
32
Protocols
Figure 6.14 The seven layers of the OSI model
![Page 33: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/33.jpg)
33
Switching Techniques and Transfer Modes Circuit Switching Message is communicated in its entirety from the
transmitting computer to the receiving computer Packet Switching
Message is divided into packets of bytes and transmitted via several nodes
![Page 34: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/34.jpg)
34
The Changing Business Environment
Cellular Phones Teleconferencing Voice Mail Facsimile
![Page 35: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/35.jpg)
35
Ethical and Societal IssuesTelecommuting: Pros and Cons Pros
Saves travel cost and time Decreases pollution May reduce unemployment. Productivity higher among telecommuters
![Page 36: 1 Information Technology Telecommunications and Networks](https://reader036.vdocument.in/reader036/viewer/2022062300/56649e305503460f94b20c77/html5/thumbnails/36.jpg)
36
Ethical and Societal IssuesTelecommuting: Pros and Cons Cons
Employers tend to pressure telecommuters to work harder than workers in the office.
No office to foster new social ties and camaraderie.
May negatively impact some segments of the economy Restaurants Downtown business and industries