Intro to Information Systems

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Telecommunications and Networks
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Chapter

• Business value of networks
• The Internet
• Network components

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Learning Objectives

1. Understand the concept of a network.
2. Apply Metcalfes law in understanding the value
   of a network.
3. Identify several major developments and trends in
   the industries, technologies, and business
   applications of telecommunications and Internet
   technologies.
4. 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

1. Identify the various transmission media and
   topologies used in telecommunications networks.
2. Understand the fundamentals of wireless network
   technologies.
3. Explain the concepts behind TCP/IP.
4. Understand the seven layers of the OSI network
   model.

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Case 1 Wireless, Wireless Everywhere

• Wireless sensor devices or motes
• Package together a circuit board, software,
  sensors and wireless radio
• Uses mesh networking software to transmit data
  from one mote to another

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Case Study Questions

1. What are some of the business benefits associated
   with using wireless networks to collect and
   transmit data?
2. What are some of the challenges being faced in
   this use of wireless technologies? What
   solutions can you offer?
3. The use of wireless networking as described in
   the case is both innovative and useful. What
   other business uses can you envision for this
   approach?

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Real World Internet Activity

• The companies mentioned in this case, Intel, IBM,
  SAIC, and GE are all familiar names often
  associated with innovative approaches to
  technology. Using the Internet,
• See if you can find examples of other companies
  that have found ways in which to apply mote
  wireless technology to business needs.

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Real World Group Activity

• One way of describing this use of wireless
  technologies is that it represents a marriage
  between RFID and wireless networking. This
  combination of enabling technologies results in
  an entirely new way of accomplishing an old task.
  In small groups,
• Brainstorm other combinations of existing
  technologies to create new approaches to existing
  business activities.

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Network Concepts

• Network
• An interconnected chain, group or system
• Number of possible connections on a network is N
  (N-1)
• Where N number of nodes (points of connections
  on the network)
• Example, if there are 10 computers on a network,
  there are 10 9 90 possible connections

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Metcalfes Law

• The usefulness of a network equals the square of
  the number of users
• On a small network, a change in technology
  affects technology only
• On a large network like the Internet, a change in
  technology affects social, political and economic
  systems

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Telecommunications

• Telecommunications
• Exchange of information in any form (voice, data,
  text, images, audio, video) over networks

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Trends in Telecommunications
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Open Systems

• Information systems that use common standards for
  hardware, software, applications and networks
• Internet networking technologies are a common
  standard for open systems
• Connectivity
• Ability of networked computers to easily access
  and communicate with each other and share
  information
• Interoperability
• The ability of an open system to enable end user
  applications to be accomplished using different
  varieties of computer systems, software packages,
  and databases provided by a variety of
  interconnected networks

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Middleware

• Any programming that serves to glue together
  two separate programs

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Digital Network Technologies

• Rapid change from analog to digital network
  technologies
• Analog voice-oriented transmission, sound waves
• Digital discrete pulse transmission
• Digital allows
• Higher transmission speed
• Larger amounts of information
• Greater economy
• Lower error rates
• Multiple forms of communications on same circuit

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Internet2

• Next generation of the Internet
• High-performance network
• In use at 200 universities, scientific
  institutions, communications corporations

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Business Value of Telecommunication Networks
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The Internet

• Over 46 million servers (2004)
• 710 945 million users (2004)
• No central computer system
• No governing body
• No one owns it

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Internet Service Provider

• ISP
• A company that specializes in providing easy
  access to the Internet
• For a monthly fee, you get software, user name,
  password and access
• ISPs are connect to one another through network
  access points

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Popular uses of the Internet
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Using the Internet for business
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Business value of the Internet
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An Intranet

• A network inside an organization
• That uses Internet technologies (such as Web
  browsers and servers, TCP/IP protocols, HTML,
  etc.)
• To provide an Internet-like environment within
  the organization
• For information sharing, communications,
  collaboration and support of business processes
• Protected by security measures
• Can be accessed by authorized users through the
  Internet

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Enterprise Information Portal
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Extranet

• Network links that use Internet technologies
• To connect the Intranet of a business
• With the Intranets of its customers, suppliers or
  other business partners

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Extranet Uses
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Case 2 Maryland and ColoradoServing their
customers without using wires

• Earth Alert Emergency Management System in
  Maryland provides
• Devices to communicate warning to individuals
  before a disaster, and
• Tools to collect timely information after a
  disaster
• Aurora Colorado
• Connects police and fire department vehicles via
  wire-less connections

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Case Study Questions

1. What is the business value of advanced mobile
   technologies to Marylands emergency management
   services?
2. In what other government services could GPS serve
   to provide business value? Give some examples.
3. Are there disadvantages or risks associated with
   the deployment of GPS systems to monitor the
   location of people? Explain.

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Real World Internet Activity

• The global positioning system (GPS) is a major
  technological achievement that has broad-reaching
  implications for business. Using the Internet,
• See if you can find other innovative uses for
  GPS.
• Good places to start familiarizing yourself with
  current accomplishments are
• The GPSWorld site at http//www.gpsworld.com/gpswo
  rld/
• The GPS Overview at http//www.colorado.edu/geogra
  phy/gcraft/notes/gps/gps_f.html

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Real World Group Activity

• The first Real World Case in this chapter
  discussed the combination of two existing
  technologies, RFID and wireless networking, to
  create an innovative business solution. In small
  groups,
• Brainstorm innovative applications of GPS and
  other existing technologies.

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Telecommunications network

• Any arrangement where a sender transmits a
  message to a receiver over a channel consisting
  of some type of medium

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Telecommunications network components

• Terminals any input/output device that uses
  networks to transmit or receive data
• Telecommunications Processors devices that
  support data transmission and reception
• Telecommunications Channels media over which
  data are transmitted and received
• Computers all sizes and types
• Telecommunications Control Software programs
  that control telecommunications activities

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Telecommunications network model
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Wide Area Network (WAN)

• Telecommunications network that covers a large
  geographic area

Source Courtesy of Cisco Systems Inc.
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Local Area Network (LAN)

• Connect computers within a limited physical area
  such as an office, classroom, or building

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Virtual Private Networks (VPN)

• A secure network that uses the Internet as its
  backbone but relies on firewalls, encryption and
  other security
• A pipe traveling through the Internet

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VPN
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Client/Server networks

• Clients End user personal computers or networked
  computers
• Interconnected by LANs
• Servers manage networks
• Processing shared between clients and servers

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Client/Server Network
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Network Computing

• Networks are the central computing resource of
  the organization
• Thin clients network computers and other clients
  provide a browser-based user interface

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Peer-to-peer networks

• Networks that connect from one PC to another PC
• Common use is the downloading and trading of files

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Peer-to-Peer Network
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Telecommunications Media

• Twisted-pair wire
• Ordinary telephone wire
• Copper wire twisted into pairs

Source Phil Degginger/Getty Images.
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Telecommunications Media

• Coaxial cable
• Sturdy copper or aluminum wire wrapped with
  spacers to insulate and protect it

Source Ryan McVay/Getty Images.
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Telecommunications Media

• Fiber-optic cable
• One or more hair-thin filaments of glass fiber
  wrapped in a protective jacket

Source CMCD/Getty Images.
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Problem of The Last Mile

• Network providers use fiber optic to provide
  backbone
• But houses are connected to the backbone via
  twisted-pair
• Cannot get the benefit of the faster, better
  technology

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Wireless Technologies

• Terrestrial microwave
• Earthbound microwave systems that transmit
  high-speed radio signals in a line-of-sight path
• Between relay systems spaced approximately
  30-miles apart
• Communications satellites
• Satellite serves as relay stations for
  communications signals
• Uses microwave radio signals

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Wireless Technologies

• Cellular and PCS telephone and pager systems
• Divide the geographic area into small areas or
  cells
• Each cell has transmitter or radio relay antenna
  to send message from one cell to another
• Wireless LANs
• Radio signals within an office or building
• Connect PCs to networks
• Bluetooth
• Short-range wireless technology
• To connect PC to peripherals such as printer

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Wireless Web

• Connect portable communications devices to the
  Internet

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Telecommunications Processors

• Modems
• Convert digital signals from a computer into
• Analog frequencies that can be transmitted over
  ordinary telephone lines

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Comparing modem and other technologies
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Internetwork Processors

• Switch makes connections between
  telecommunications circuits in a network
• Router intelligent communications processor
  that interconnects networks based on different
  protocols
• Hub a port switching communications processor
• Gateway connects networks using different
  communications architectures

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Communications Processors
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Telecommunications Processors

• Multiplexer
• Allows a single communications channel to carry
  simultaneous data transmissions from many
  terminals

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Telecommunications Software

• Used by servers and other computers to manage
  network performance
• Network Operating Systems
• Middleware

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Network management functions

• Traffic Management manage network resources and
  traffic to avoid congestion and optimize service
  levels to users
• Security provide authentication, encryption,
  firewall, auditing and enforcement
• Network Monitoring troubleshoot and watch over
  the network, informing network administrators of
  potential problems before they occur
• Capacity Planning survey network resources and
  traffic patterns and users needs to determine
  how best to accommodate the needs of the network
  as it grows and changes

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Network Topologies

• Topology structure of a network
• Star ties end user computers to a central
  computer
• Ring ties local computer processors together in
  a ring on a relatively equal basis
• Bus local processors share the same
  communications channel

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Network Topologies
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Network Architectures Protocols

• Protocol standard set of rules and procedures
  for the control of communications in a network
• Network Architecture
• Master plan of standard protocols, hardware,
  software and interfaces between end users and
  computer systems
• Goal of promoting an open, simple, flexible, and
  efficient telecommunications environment

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OSI TCP/IP Models

• Open Systems Interconnection (OSI) Model
• A seven-layer model that serves as a standard
  model for network architectures
• Model for how messages should be transmitted
  between two points in a network
• Each layer adds functions
• Transmission Control Protocol / Internet Protocol
  (TCP/IP)
• A five layer telecommunications protocol used by
  the Internet

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OSI TCP/IP Models
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Internet Telephony

• Using an Internet connection to pass voice data
  using IP
• Voice over IP (VoIP)
• Skips standard long-distance phone charges

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Bandwidth

• Bandwidth
• Frequency range of a telecommunications channel
• Determines transmission rate
• Classified in bits per second (bps)
• Transmission Rates
• Narrow-band low-speed
• Broadband high-speed

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Transmission Speeds
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Switching Alternatives

• Circuit Switching
• Switch opens a circuit to establish a link
  between a sender and receiver
• it remains open until the communication session
  is completed
• Packet Switching
• Break messages into groups called packets
• Transmit packets separately

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Network Interoperability

• Ensure that anyone anywhere on one network
• Can communicate
• With anyone anywhere on another network
• Telecommunications as discussed in this chapter
  wouldnt be possible without interoperability

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Case 3 Voice Over IP is the Real Thing

• VoIP works by
• Digitizing a voice signal,
• Chopping it into packets, and
• Sending them over a companys network or the
  Internet
• Packets are reassembled at the destination
• Minnesota Department of Labor has cut its monthly
  phone bill in half

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Case Study Questions

1. What are the main benefits that can be gained by
   companies that switch to VoIP systems?
2. What are some of the major cost factors that may
   limit a positive rate of return from investments
   in VoIP projects?
3. Should more companies switch to VoIP systems?
   Visit the websites of Avaya and Cisco Systems to
   view their VoIP news, products, and services to
   help you answer.

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Real World Internet Activity

• VoIP is becoming a highly competitive marketplace
  for the delivery of services and the development
  of software to support the process. Using the
  Internet,
• See if you can identify who the major players are
  in this market.
• Where do you see the next significant development
  for VoIP?
• Do you think the concept will eventually replace
  conventional telephone technologies? Why or why
  not?

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Real World Group Activity

• The original concept for the Internet never
  included many of the uses we have found for it
  and consider commonplace today. While Internet2
  is on the horizon, we need to think about what
  uses we may want from the Internet in the future.
  In small groups,
• Brainstorm how we might use the Internet in the
  future.
• Do we run the risk of overloading the Internet or
  relying on it too much?