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Chapter 8
Essentials of Management Information Systems, 6e
Chapter 8 Telecommunications, Networks, and Wireless Computing
Telecommunications, Networks,
and Wireless Computing
8.1
© 2005 by Prentice Hall
Management Challenges
1. Selecting appropriate technologies for enterprise
networking
2. Managing bandwidth
8.2
The Corporate Telecommunications System
Telecommunications System
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8.3
Facilitation of electronic communication
Telephone systems
Broadcast and cable TV
Radio, satellite, and local area networks
Internet
Analog or digital
The Corporate Telecommunications System
Features of Contemporary Telecommunications Systems
Three Major Developments Shaping
Contemporary Systems
1. Client/server computing
2. Packet switching
3. TCP/IP and other communications standards
8.4
The Corporate Telecommunications System
A corporate telecommunications system
Figure 8-1
8.5
The Corporate Telecommunications System
Features of Contemporary Telecommunications Systems
Client/Server Computing
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Powerful personal computers connect to network
with one or more server computers
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Has extended networking to parts of business
that could not be served by centralized
architecture
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Processing load balanced over many smaller
machines
8.6
The Corporate Telecommunications System
Features of Contemporary Telecommunications Systems
Packet Switching
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Messages broken into “packets” before
transmission
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Packets include destination and error-checking
information
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Packets travel independently using routers;
reassembled into original message at destination
8.7
The Corporate Telecommunications System
Packet-switched networks and packet communications
Figure 8-2
8.8
The Corporate Telecommunications System
Features of Contemporary Telecommunications Systems
TCP/IP
Transmission Control Protocol/Internet Protocol
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8.9
Open suite of protocols for connectivity
developed in 1970s
Provides standards for breaking messages into
packets, routing them to destination addresses,
and reassembling them at end
Allows for communication regardless of
hardware/software
The Corporate Telecommunications System
Features of Contemporary Telecommunications Systems
TCP/IP: Four-Layer Reference Model
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Application layer: Communication between applications
and other layers
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Transport layer: Acknowledging and sequencing packets
to/from application
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Internet layer: Addressing, routing, packaging data
packets
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Network interface layer: Placing packets on and
receiving them from network medium
8.10
The Corporate Telecommunications System
The Transmission Control Protocol/Internet Protocol (TCP/IP) reference model
Figure 8-3
8.11
The Corporate Telecommunications System
Transmission Media
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Twisted wire
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Coaxial cable:
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8.12
Copper wire twisted in pairs
Older analog transmission medium
Can be used for digital signals
Modems used for translating analog to digital
Insulated copper wire
Faster, more interference-free than twisted pair
Difficult to install; doesn’t support analog signals
The Corporate Telecommunications System
Functions of the modem
Figure 8-4
8.13
The Corporate Telecommunications System
Transmission Media
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Fiber optics
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8.14
Strands of clear glass fiber bound into cables
Data sent as pulses of light
Faster, lighter, more durable
Difficult to install; more expensive
Used in high-capacity optical networks
Currently slowed by need to convert back and
forth to electrical data
Can use multiplexing; allows one channel to carry
several transmissions
The Corporate Telecommunications System
Transmission Media
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Wireless Transmission
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8.15
Use electromagnetic spectrum
Microwave and infrared use high-frequency radio
signals
Paging systems, cellular telephones, PDAs, mobile
data networks
Wireless communication requires compatible
standards
Security/privacy issues
The Corporate Telecommunications System
Frequency ranges for communication media and devices
Figure 8-5
8.16
The Corporate Telecommunications System
Amoco’s satellite transmission system
Figure 8-6
8.17
The Corporate Telecommunications System
Transmission Media
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Transmission Speed
Bps: Bits per second
Baud rate: Rate of signal changes
One signal change = cycle
Transmission capacity is function of frequency
Bandwidth: Range of frequencies
accommodated on a particular channel
The Corporate Telecommunications System
Transmission Media
Transmission Speed
8.19
Twisted wire
Up to 100 Mbps
Microwave
Up to 200+ Mbps
Satellite
Up to 200+ Mbps
Coaxial cable
Up to 200 Mbps
Fiber-optic cable
Up to 6+ Tbps
Low cost
High cost
Communications Networks
Local Area Networks
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8.20
Connects computers and other digital devices
within 2000 ft radius
Cabling or wireless technology links computers,
network interface cards, and software
Ethernet
Network Operating System (NOS)
Client/server or peer-to-peer architecture
Star, bus, and ring topologies
Communications Networks
A local area network (LAN)
Figure 8-7
8.21
Communications Networks
Network topologies
Figure 8-8
8.22
Communications Networks
Wireless Networks: Wi-Fi and Bluetooth
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8.23
Use radio waves to connect stations
802.11b: Current standard; 54 Mbps in 2.4 GHz
range
Infrastructure mode: Wireless devices
communicate with wired LAN via access points
Ad-hoc mode: Peer-to-peer mode; wireless
devices communicate with each other directly
Communications Networks
An 802.11 wireless LAN
Figure 8-9
8.24
Communications Networks
Wireless Networks: Wi-Fi and Bluetooth
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Hot spot: Geographic location in which an
access point provides public Wi-Fi network
service
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Bluetooth: Standard for wireless personal area
networks that can transmit up to 722 Kbps
within 10-meter area
8.25
Communications Networks
Wide Area Networks
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Span broad geographic distances
Can consist of combination of:
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8.26
Switched lines
Dedicated lines
Microwave
Satellite communications
Private WANs expensive to support
Communications Networks
Wide Area Networks
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Metropolitan Area Network (MAN)
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Value-Added Networks
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8.27
Scope between LAN and WAN
Limited distance; faster and less expensive than
WAN
Private, third-party managed, data only networks
Subscription basis
Communications Networks
Window on Organizations
Is the World Falling for Wi-Fi?
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What management, organization, and technology
factors account for different patterns of Wi-Fi
adoption in various countries?
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What value can Wi-Fi service provide to
businesses?
8.28
Communications Networks
Broadband Network Services and Technologies
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8.29
Frame relay
Asynchronous transfer mode (ATM)
Integrated Services Digital Network (ISDN)
Digital subscriber line (DSL)
T1 line
Network convergence
Electronic Business and Electronic Commerce Technologies
Electronic Mail and Groupware
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E-mail
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Groupware
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8.30
Eliminates telephone tag and costly long-distance
telephone charges
Enables work groups at different locations to
participate in discussion forums and work on
shared documents and projects
Electronic Business and Electronic Commerce Technologies
Window on Management
Monitoring Employees on Networks:
Unethical or Good Business?
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Should managers monitor employee e-mail and
Internet usage? Why or why not?
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Describe an effective e-mail and Web use policy
for a company.
8.31
Electronic Business and Electronic Commerce Technologies
Voice Mail and Fax
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Voice mail
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Fax
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8.32
Digitizes spoken message and transmits it over a
network
Digitizes and transmits documents over telephone
lines
Electronic Business and Electronic Commerce Technologies
Teleconferencing, Dataconferencing, and Videoconferencing
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8.33
Teleconferencing
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Ability to confer with a group of people
simultaneously
Data conferencing
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Two or more users can edit and modify data files
simultaneously
Videoconferencing
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Participants are able to see each other over video
screens
Electronic Business and Electronic Commerce Technologies
Digital Information Services, Distance Learning, and E-Learning
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Digital Information Services:
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Distance learning
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Education or training delivered over a distance to
individuals in one or more locations
E-learning
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8.34
Online services providing general and business
information, such as LexisNexis, AOL, Dow Jones
News
Instruction delivered online using the Internet or
private networks
Electronic Business and Electronic Commerce Technologies
Electronic Data Interchange
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Computer-to-computer exchange between two
organizations of standard transaction documents,
such as invoices, purchase orders
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Minimizes paper-handling and data input;
lowers transaction costs
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Transmits structured data with fields, unlike email
8.35
Electronic Business and Electronic Commerce Technologies
Electronic data interchange (EDI)
Figure 8-10
8.36
Developing a Business-Driven Telecommunications Plan
Implementation Issues: Seven Factors
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8.37
Distance
Services
Points of access
Utilization
Cost
Security
Connectivity
Chapter 8 Case Study
Will New Systems Keep Delta Flying?
1. Analyze Delta using the competitive forces and
value chain models.
2. What is Delta’s business strategy? What is the
role of information systems and
telecommunications technology in this strategy?
8.38
Chapter 8 Case Study
Will New Systems Keep Delta Flying?
3. Assess Delta’s Digital Nervous System (DNS)
effort. What value does it provide the company?
How does it support Delta’s business strategy?
4. What problems at Delta can be solved with
information systems? What problems cannot be
solved with systems?
8.39