Chapter 6
Telecommunications and
Networks
McGraw-Hill/Irwin
Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved.
Learning Objectives
Understand the concept of a network
Apply Metcalfe’s Law in understanding the
value of a network.
Identify several major developments and
trends in the industries, technologies, and
business applications of telecommunications
and Internet technologies.
Provide examples of the business value of
Internet, intranet, and extranet applications.
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Learning Objectives
 Identify the basic components, functions, and types of
telecommunications networks used in business.
 Explain the functions of major components of
telecommunications network hardware, software,
media, and services.
 Explain the concept of client/server networking.
 Understand the two forms of peer-to-peer networking.
 Explain the difference between digital and analog
signals.
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Learning Objectives
 Identify the various transmission media and topologies
used in telecommunications networks.
 Understand the fundamentals of wireless network
technologies.
 Explain the concepts behind TCP/IP.
 Understand the seven layers of the OSI network model.
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Section 1
Telecommunications and Networks
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II. The Concept of a Network
The Concept of a Network – an
interconnected/interrelated system
Metcalf’s Law – the utility (use) of a
network equals the square of the number of
users
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IV. The Business Value of
Telecommunications Networks
Cut costs, shorten lead/response times,
improve collaboration, support e-commerce
The Internet Revolution – a “network of networks”,
the largest and most important network, constantly
expanding
Internet Service Providers (ISP) – provides easy
access to the Internet
Internet Applications – browsing the Net, email,
instant messaging
Business Use of the Internet – the Internet adds
value to every prt of the business cycle
The Business Value of the Internet
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V. The Role of Intranets
Intranet – a private internal network using
Internet technologies
 The Business Value of Intranets – an enterprise information
portal supporting communications and collaboration
 Communications and Collaboration – improved by Intranets
 Web Publishing – developing and publishing hyperlinked
multimedia documents
 Business Operations and Management – develop/deploy
critical applications supporting operations and managerial
decision making
 Intranet Portal Management – managed by IS/IT professionals
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VI. The Role of Extranets
Extranet – A private network using Internet
technologies (intranet) opened to select
external entities for purposes of
communications
Purpose – interconnect the business with its
suppliers/customers/business partners
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Section 2
Telecommunications Network Alternatives
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II. Telecommunications Network
Model – 5 basic components:
Terminals – any input/output device to
transmit/receive data
Telecommunications Processors – support data
transmission/reception between terminals
Telecommunications Channels – media over which
messages are sent
Computers – interconnected by
telecommunications networks
Telecommunications control software – programs
to control telecommunications activities and
functions
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III. Types of Telecommunications
Networks
A Network is defined by its geographic area
and who owns the equipment
Wide Area Networks (WAN) – between cities/large
geographic areas, LANs connected by common
carrier or leased lines
Metropolitan Area Networks (MAN) – LANs
connected over a specific geographical area
Local Area Networks (LAN) – equipment owned by
the firm, short distances, usually within a single
building (or room)
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III. Types of Telecommunications
Networks
Virtual Private Networks (VPN) – a network using
the Internet as a backbone but incorporating
security for privacy
Client/Server Networks – a powerful, central
computer (server) providing information and
processing (services) to multiple end-user
computers (clients)
Network Computing – a minimally-powered
browser-based computer obtains its data and
processing from the Internet
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IV. Digital and Analog Signals
Analog (continuous) – any value
between the maximum/minimum value
is possible (e.g., any frequency between
20hz and 20K hz)
Digital (discrete) – only certain values
are permitted (e.g., 0 and 1)
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IX. Network Topologies
 Topologies – the structure (or “look”) of a network; 3
basic types: bus, ring, star
 Protocols – formal rules for communications
 Network Architectures
 The Internet’s TCP/IP – Transmission Control
Protocol/Internet Protocol – the standard protocol for
the Internet
 Voice Over IP – Internet telephony, replaces publicswitched service
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