Chapter 7
Telecommunications,
the Internet, and
Wireless Technology
7.1
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
LEARNING OBJECTIVES
• Describe the features of telecommunications
networks and identify key networking technologies.
• Evaluate alternative transmission media, types of
networks, and network services.
• Demonstrate how the Internet and Internet technology
work and how they support communication and ebusiness.
7.2
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
LEARNING OBJECTIVES (cont’d)
• Identify and describe the principal technologies and
standards for wireless networking, communication,
and Internet access.
• Assess the business value of wireless technology and
important wireless applications in business.
7.3
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Hyatt Regency Osaka Uses Wireless Networking for High-Touch Service
• Problem: Overcoming poor location and steep
competition.
• Solutions: Deploy IP network, wireless LAN, and wireless
clients with links to customer database to increase
service and revenue.
• Wireless mobile access to customer systems and
wireless data and voice services enable employees to
work more efficiently and focus on customers.
• Demonstrates IT’s role in providing superior customer
service and redesigning processes and job functions.
• Illustrates digital technology’s ability to overcome
business weaknesses by creating new strengths.
7.4
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
• Networking and communication trends
• Convergence of telephone and computer networks
into single digital network using Internet standards
• Telecommunications providers offering multiple services: Data,
cable, Internet, voice
• Both voice and data networks have become more
powerful, more portable, and less expensive
• Broadband connections of 1Mbps
• Growth of wireless broadband platforms, wireless
Internet access
7.5
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
• Most basic computer network: Two or more interconnected
computers
• Major hardware, software, transmission components
used in simple network:
•
•
•
•
•
Client computer
Dedicated server computer
Network interfaces (NICs)
Network operating system (NOS)
Hub or switch
• Routers:
• Device used to communicate with other networks
7.6
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
Components of a Simple Computer Network
Illustrated here is a very simple computer network, consisting of computers, a network operating system
residing on a dedicated server computer, cable (wiring) connecting the devices, network interface cards (NIC),
switches, and a router.
Figure 7-1
7.7
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
• Networks in large companies may include
• Hundreds of local area networks (LANs) linked to firmwide
corporate networks
• Multiple powerful servers
• Corporate Web site, corporate intranet, extranet
• Back-end systems for sales, financial, purchasing transactions
• Telephone network, videoconferencing
• Mobile WiFi network
• Key issue: Integration of disparate systems
• Alleviated as networks digitize, use Internet standards
7.8
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
Corporate Network Infrastructure
Today’s corporate network
infrastructure is a collection
of many different networks
from the public switched
telephone network; to the
Internet; to corporate local
area networks linking
workgroups, departments,
or office floors.
7.9
Figure 7-2
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
• Key digital networking technologies
• Client/server computing
• Clients linked through network controlled by server computer
• Packet switching
• Method of slicing digital messages into packets, sending packets along
different communication paths as they become available, and then
reassembling packets once they arrive at their destinations
• TCP/IP and connectivity standards
• Protocol: Set of rules and procedures governing transmission
of information between two points in network
• TCP/IP: Suite of protocols
7.10
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
Packet-Switched Networks and
Packet Communications
Data are grouped into
small packets, which are
transmitted
independently over
various
communications
channels and
reassembled at their
final destination.
7.11
Figure 7-3
© 2007 by Prentice Hall
Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
•
7.12
TCP/IP: Suite of protocols developed for U.S. Dept. of Defense
•
Transmission Control Protocol (TCP): Handles movement of data
between computers
•
Internet Protocol (IP): Handles assembly, delivery, disassembly of
packets
•
TCP/IP allows two computers of different hardware and software
platforms to communicate
•
Four-layer TCP/IP reference model
1.
Application layer
2.
Transport layer
3.
Internet layer
4.
Network interface layer
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World
The TCP/IP Reference Model
This figure illustrates
the four layers of the
TCP/IP reference model
for communications.
7.13
Figure 7-4
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Signals: digital vs. analog
• Analog: Represented by continuous waveform
• Digital: Discrete, binary waveform
• Data as strings of two states: one bit, zero bits / on-off
electrical pulses
• Modem needed to translate between analog and digital
• Types of networks (geographic scope)
•
•
•
•
7.14
Local area network (LAN)
Campus area network (CAN)
Metropolitan area network (MAN)
Wide area network (WAN)
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
Functions of the Modem
A modem is a device that translates digital signals from a computer into analog form so that they can
be transmitted over analog telephone lines. The modem also translates analog signals back into
digital form for the receiving computer.
Figure 7-5
7.15
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Ethernet: Dominant LAN standard at physical network
level
• Types of networks (network architecture)
• Peer-to-peer or client/server
• Types of networks (topology)
• Star: All network components connect to single hub
• Bus: Signals travel in both directions along single transmission
segment
• Most common Ethernet topology
• Ring: Connects network components in closed loop
7.16
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
Network Topologies
The three basic network topologies are the bus, star, and ring.
Figure 7-6
7.17
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Physical transmission media
• Twisted wire
• Pairs of twisted copper wire
• Older type of transmission medium
• Most common LAN cabling: Cat5 cable
• Coaxial cable
• Single, thickly insulated copper wire
• Used for longer runs
7.18
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Physical transmission media
• Fiber optics and optical networks
• Strands of clear glass fiber
• Used for Internet backbone
• Optical networks can boost capacity by using multiplexing
(DWDM) - using different wave lengths to carry separate
streams of data over same strand
7.19
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Wireless transmission media
• Microwave systems
• High-frequency radio signals that follow straight line and require
transmission stations or satellites to act as relay
• Cellular telephones
• Radio towers placed in adjacent geographic areas (cells)
7.20
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
BP Amoco’s Satellite Transmission System
Satellites help BP Amoco transfer seismic data between oil
exploration ships and research centers in the United States.
Figure 7-7
7.21
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Transmission speed
• Bits per second (bps): Used to measure total amount
of data that can be transmitted
• Hertz (cycles per second): Frequency of medium,
affects transmission capacity
• Bandwidth: Difference between highest and lowest
frequencies that can be accommodated on channel
7.22
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Broadband network services and technologies
• Frame relay (56 Kbps to 40+ Mbps)
• Packages data into frames for high-speed transmission over reliable
circuits that require less error checking than packet switching
• Asynchronous Transfer Mode (ATM) (1.5 Mbps to 9+Gbps)
• Parcels data into 53-byte cells for high-speed transmission
• Can transmit data, video, and audio over same network
• Integrated Services Digital Network (ISDN) (128 Kbps to 1.5
Mbps)
• Dial-up network access standard that can integrate voice, data, and
video services
7.23
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
Communications Networks
• Broadband network services and technologies
• Digital subscriber line (DSL) (1 Mbps – 9 Mbps)
• Dedicated telephone network broadband Internet access
• Cable Internet connections (Up to 10 Mbps)
• Dedicated cable network broadband access
• T lines (1.5 Mbps to 45 Mbps)
• Dedicated lines for high-speed data transmission and Internet
connection
7.24
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• What is the Internet?
• World’s most extensive public communication system, rivaling
global telephone system
• World’s largest implementation of:
• Client/server network
• Internetworking
• Internet service provider:
• Commercial organization with permanent connection to Internet
• Sells temporary connections to retail subscribers
7.25
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Internet addressing
• IP address
• Assigned to each computer on Internet
• 32-bit number: four strings of numbers ranging from 0 to 255
separated by periods
• E.g. 207.46.250.119
• Messages decomposed into packets, each carrying
destination IP address
7.26
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Domain Name System
• Converts IP addresses to domain names
• DNS servers maintain database of domain names mapped to IP
addresses
• Domains: E.g. sales.google.com
• Root domain (“.”)
• Top-level domain (.gov, .com, .edu, etc.)
• Second-level domain (e.g. “google”)
• Third-level domains/hosts (“computer1.sales.google.com”)
7.27
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
The Domain Name System
The Domain Name
System is a hierarchical
system with a root
domain, top-level
domains, second-level
domains, and host
computers at the third
level.
7.28
Figure 7-8
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Internet architecture
• Trunk lines: High-speed backbone networks owned by longdistance telephone companies (network service providers) or
national governments
• Regional networks lease access to ISPs, private companies,
government institutions
• Regional telephone, cable companies lease access to retail users
and businesses
7.29
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
Internet Network Architecture
The Internet backbone
connects to regional networks,
which in turn provide access to
Internet service providers,
large firms, and government
institutions. Network access
points (NAPs) and metropolitan
area exchanges (MAEs) are
hubs where the backbone
intersects regional and local
networks and where backbone
owners connect with one
another. MAEs are also
referred to as Internet
Exchange Points.
7.30
Figure 7-9
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Internet governance
• Internet policies established by several professional
organizations and government bodies
• IAB: Defines overall structure of Internet
• ICANN: Assigns IP addresses
• W3C: Sets programming standards, HTML standards for Web
• These organizations influence government agencies,
network owners, ISPs, and software developers
• Internet must conform to local national law and
technical infrastructure
• Internet paid for by connection services and fees
7.31
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• IPv6
• IPv4 (32 bit addresses) provides 4.5 billion addresses
• Less than one address for each of Earth’s 6.5 billion
• IPv6 (128 bit addresses) will provide 3.4 X 1038 addresses
• Millions of addresses for each person
• Internet2 and Next-Generation Internet (NGI)
• Consortia of universities, businesses, government agencies
addressing current shortcomings of Internet
• Better performance, more bandwidth
• More effective routing
• Advanced applications for distributed computing, etc.
7.32
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Internet services
• Client/server technology
• Client:
• Software (e.g. Web browsers) on personal computers or
information appliances
• Servers:
• Store data (e-mails, Web pages)
• Transfer data to clients
• Run services, implemented by one or more software
programs, that clients can access
• E.g. Telnet, FTP, World Wide Web, newsgroups, chat
7.33
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
Client/Server Computing on the Internet
Client computers running Web browser and other software can access an array of services on servers over the Internet. These services
may all run on a single server or on multiple specialized servers.
Figure 7-10
7.34
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• World Wide Web: Most popular Internet service
• Web pages: Formatted using Hypertext Markup Language
(HTML) with embedded links that connect documents to one
another and that also link pages to other objects, such as sound,
video, or animation files
• Hypertext Transfer Protocol (HTTP): Communications
standard used to transfer pages on Web
• Uniform resource locator (URL): Full address of web page,
including protocol, domain name, directory path, and file name
• E.g.: http://www.megacorp.com/content/features/082602.html
7.35
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Web servers: Software for locating and managing stored
Web pages, typically run on dedicated computers
• E.g. Apache HTTP Server, Microsoft IIS
• Web site: Collection of Web pages linked to home page
• Webmaster: Person in charge of organization’s Web site
• Search engines: Allow finding information on Web of 50
billion+ pages nearly instantly
• Serve as major portals to Web
• Early search engines: Simple keyword indexes of visited pages
• Yahoo!: Originally organized favorite Web sites into directory lists
7.36
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Search engines:
• Google: Utilized new page ranking system and indexed
combinations of words
• Search engine marketplace very competitive
• Search engines have become major shopping tools
• Search engine marketing:
• Search engine includes paid, sponsored links and advertisements in
search results
• Fastest growing form of Internet advertising
• Shopping bots:
• Use intelligent agent software for searching Internet for shopping
information
7.37
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
Major Web Search Engines
Google is the most popular search engine on the Web, handling nearly 50 percent of all Web searches.
Figure 7-11
7.38
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
How Google Works
Figure 7-12
The Google search
engine is
continuously
crawling the Web,
indexing the content
of each page,
calculating its
popularity, and
storing the pages so
that it can respond
quickly to user
requests to see a
page. The entire
process takes about
one-half second.
7.39
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Web 2.0
• Second-generation interactive Internet-based services
• Mashups: Software services that mix and match content or
software components to create something entirely new
• Blog: informal chronological Web site where subscribing
individuals can publish stories, opinions, and links to other Web
sites
• RSS (Rich Site Summary or Really Simple Syndication):
Syndicates Web site content so it can be pulled from Web sites
and fed automatically to subscribed users
• Wikis: Collaborative Web sites where visitors can add, delete, or
modify content on site, including work of previous authors
7.40
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Intranets: Private networks using Internet standards
• Protected from public visits by firewalls
• Extranets: Limited area of intranet designed for access by
authorized vendors and customers
• Technologies and tools for communication and ebusiness
• E-mail
• Chat, instant messaging
• Electronic discussions
• Groupware
• Electronic conferencing
7.41
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
Monitoring Employees on Networks: Unethical or Good
Business?
• Read the Interactive Session: Management, and then
discuss the following questions:
• Should managers monitor employee e-mail and Internet
usage? Why or why not?
• Describe an effective e-mail and Web use policy for a
company.
7.42
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Internet telephony:
• Telephone voice transmission over Internet or private networks
• Voice over IP (VoIP): Uses Internet Protocol (IP) to deliver voice
information using packet switching, avoiding tolls charged by local
and long-distance telephone networks
• Fastest-growing form of telephone service in United States
• Can reduce communication and network management costs by 20
to 30 percent
• Flexible technology: Phones can be added or moved to different
offices without rewiring or reconfiguring network
7.43
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
How IP Telephony Works
An IP phone call digitizes and breaks up a voice message into data packets that may travel along different routes before being
reassembled at the final destination. A processor nearest the call’s destination, called a gateway, arranges the packets in the
proper order and directs them to the telephone number of the receiver or the IP address of the receiving computer.
Figure 7-13
7.44
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
• Virtual private networks
• Secure, encrypted, private network configured within
public network, like Internet
• Provide network infrastructure for combining voice and
data networks
• Can be established with different, competing protocols
• E.g. Point-to-Point Tunneling Protocol (PPTP)
• Tunneling: Packets of data are encrypted and wrapped inside
IP packets
7.45
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Internet
A Virtual Private Network Using the Internet
This VPN is a private network of computers linked using a secure “tunnel” connection over the Internet. It protects data
transmitted over the public Internet by encoding the data and “wrapping” them within the Internet Protocol (IP). By adding a
wrapper around a network message to hide its content, organizations can create a private connection that travels through the
public Internet.
Figure 7-14
7.46
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wireless devices: Have become portable computing
platforms
• Cell phones
• Laptops
• Handhelds
• Personal digital assistants (PDAs)
• E-mail handhelds
• Smart phones
• Cellular systems:
• Mobile phones enable millions to communicate and access
Internet in countries where conventional phone or Internet service
is expensive or unavailable. More mobile phones than PCs (3
billion vs 1 billion)
7.47
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Cellular standards
• Global system for mobile communication (GSM)
• Europe, most of world, and some U.S. systems (AT&T)
• Code Division Multiple Access (CDMA)
• A widely used standard in U.S. (Verizon)
• Cellular Generations:
• 384 Kbps, good for e-mail, and OK at downloading Web pages.
• 3G (third generation) networks: 384 Kbps to 2 Mbps, acceptable
for broadband access
• 2.5G networks: Interim solution; 30 - 144 Kbps. iPhone uses AT&T
EDGE 2.G network maximum speed 236; actual about 80 Kbps
7.48
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Mobile wireless standards for Web access
• Wireless Application Protocol (WAP)
• System of protocols, technologies enabling cell phones and
other devices with tiny display screens, low bandwidth, and
minimal memory to access Web-based information and services
• Uses:
• Wireless markup language (WML) based on XML
• Microbrowsers
• WAP gateway to translate Web content into WML for mobile
devices
• Google Mobile and Yahoo! Mobile pages
7.49
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Mobile wireless standards for Web access
• I-mode
• Japan’s DoCoMo mobile phone network’s wireless
service
• Uses compact HTML to deliver content
• Easier for business to convert Web sites for mobile
access
• Limited geographic adoption to Asia
7.50
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
WAP Versus I-Mode
WAP and i-mode use
alternative standards
for accessing
information from the
wireless Web.
7.51
Figure 7-15
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Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wireless computer networks and Internet
access
• Institute of Electrical and Electronics Engineers (IEEE)
Standards for wireless networks
• IEEE 802.15: PANs, Bluetooth
• IEEE 802.11: LANs, Wi-Fi
• IEEE 802.16: MANs, WiMax
7.52
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Bluetooth:
• IEEE 802.15
• Useful for personal area networks (PANs)
• Links up to eight devices within 10-meter area using
low-power, radio-based communication
• Transmits up to 722 Kbps in 2.4-GHz band
• Used for wireless keyboards, mice, cell phones, PDAs,
printers
7.53
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
A Bluetooth Network (PAN)
Bluetooth enables a variety of devices, including cell phones, PDAs, wireless keyboards and mice, PCs, and
printers, to interact wirelessly with each other within a small 30-foot (10-meter) area. In addition to the links
shown, Bluetooth can be used to network similar devices to send data from one PC to another, for example.
Figure 7-16
7.54
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wi-Fi
• IEEE 802.11 standards
• 802.11a: 54 Mbps, 5 GHz,
• 802.11b: 11 Mbps, 2.4 GHz
• 802.11g: 54 Mbps, 2.4 GHz, compatible with 802.11b
• 802.11n: emerging standard, greater than 200 Mbps
• Modes:
• Infrastructure mode: Wireless devices communicate with wired LAN
using access points (device with radio receiver/transmitter)
• Ad hoc mode: Wireless devices communicate directly to each other
• Wireless communication requires client to have wireless NICs or
embedded chips to receive Wi-Fi signals
7.55
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
An 802.11 Wireless LAN
Mobile laptop computers
equipped with wireless NICs link
to the wired LAN by
communicating with the access
point. The access point uses
radio waves to transmit network
signals from the wired network
to the client adapters, which
convert them into data that the
mobile device can understand.
The client adapter then transmits
the data from the mobile device
back to the access point, which
forwards the data to the wired
network.
7.56
Figure 7-17
© 2007 by Prentice Hall
Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wi-Fi and wireless Internet access
• IEEE 802.11 standard provides wireless Internet
access
• Access point plugs into Internet connection
• Wi-Fi hotspots:
• One or more access points in public space to provide maximum
wireless coverage
• Some are free, others require registration/fees
7.57
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wi-Fi drawbacks
• Weak security (especially when not secured!)
• No roaming from hotspot to hotspot
• Susceptibility to interference from nearby
systems operating in same spectrum
• Wireless phones, microwave ovens, other wireless
LANs
7.58
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• WiMax
• Worldwide Interoperability for Microwave Access
• IEEE 802.16 standard
• Access range up to 31 miles
• Data transfer up to 75 Mbps
• WiMax antennas are powerful enough to beam highspeed Internet connections to rooftop antennas of
homes and businesses that are miles away
7.59
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Broadband cellular wireless and emerging wireless
services
• 2.5G and 3G networks configured to provide anytime broadband
access for PCs and handhelds
• EV-DO (Evolution Data Optimized): Technology providing cellular
wireless Internet access at 200-400 Kbps maximum.
• Basis for Verizon’s and Sprint’s wireless services
• Many cell phones and mobile devices can switch from one type of
network to another, are Bluetooth-capable, etc.
7.60
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Radio Frequency Identification (RFID) systems
• Use tiny tags (transponders) with embedded microchips that
transmit radio signals over short distance to RFID readers
• Operate in various unlicensed frequency bands
• Low frequency systems have short reading ranges (up to few feet)
• Requires special middleware to filter, aggregate RFID data
• Usually requires companies to upgrade hardware and software to
handle massive amounts of data produced by RFID systems
• Used to track movement of goods through supply chain
• RFID systems can track each pallet, lot, or even unit item in shipment
7.61
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
How RFID Works
RFID uses low-powered radio transmitters to read data stored in a tag at distances ranging from 1 inch to 100 feet.
The reader captures the data from the tag and sends them over a network to a host computer for processing.
Figure 7-18
7.62
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wireless sensor networks (WSNs)
• Networks of interconnected devices embedded in physical
environment
• Provide measurement of many points over large spaces
• Devices have built-in processing, storage, radio-frequency sensors
and antennas
• Range from hundreds to thousands of nodes
7.63
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
• Wireless sensor networks (WSNs)
• May use tiered architecture:
• Progressing from low-level sensors to high-level data
aggregation, analysis, and storage
• Uses:
• Monitoring environmental changes, e.g. tire pressure in your car
• Monitoring traffic or military activity
• Protecting property
• Operating machinery and vehicles
• Establishing security perimeters
• Monitoring supply chain management
7.64
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Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
A Wireless Sensor Network for a Security System
Figure 7-19
Each level of this wireless
sensor network handles
different types of sensing.
Lower-level sensors for
monitoring events, such as
doors opening and closing,
motion, and breakage of
windows and doors, are
complemented by a small
group of more advanced
sensors placed in key
locations, such as cameras
and acoustic and chemical
detectors.
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© 2007 by Prentice Hall
Management Information Systems
Chapter 7 Telecommunications, the Internet, and Wireless Technology
The Wireless Revolution
Wal-Mart Grapples with RFID
• Read the Interactive Session: Organizations, and then
discuss the following questions:
• How is RFID technology related to Wal-Mart’s business
model? How does it benefit suppliers?
• What management, organization, and technology factors
explain why Wal-Mart suppliers had trouble implementing
RFID systems?
• What conditions would make adopting RFID more favorable
for suppliers?
• Should Wal-Mart require all its suppliers to use RFID? Why or
why not? Explain your answer.
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© 2007 by Prentice Hall