Transcript Tech Briefing

Technology
Briefing
Advanced Topics and Trends in Managing the
Information Systems Infrastructure
TB-1
“Information networks straddle
the world. Nothing remains
concealed. But the sheer volume
of information dissolves the
information. We are unable to
take it all in.”
Gunter Grass,
Nobel Laureate
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Learning Objectives
TB-2
1. Discuss advanced information systems hardware
concepts.
2. Describe advanced topics related to systems and
application software, as well as the characteristics of various
types of programming languages and application
development environments.
3. Describe network software and hardware,
including media access control, network topologies,
and protocols, as well as advanced Internet concepts.
4.
Explain advanced database management
concepts.
IS Today (Valacich & Schneider)
3/27/2017
Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall
Learning Objectives
TB-3
1. Discuss advanced information systems hardware
concepts.
2. Describe advanced topics related to systems and
application software, as well as the characteristics of various
types of programming languages and application
development environments.
3. Describe network software and hardware,
including media access control, network topologies,
and protocols, as well as advanced Internet concepts.
4.
Explain advanced database management
concepts.
IS Today (Valacich & Schneider)
3/27/2017
Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall
Information Systems Hardware
TB-4
 Input Devices
 Used to enter information into a computer
 Processing Devices
 Transform inputs into outputs
 Output Devices
 Deliver information to users in a usable format
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Input Devices
TB-5
 Entering text and
numbers
 Keyboard (QWERTY)
Traditional
 Ergonomic
 Virtual

Source: http://www.sforh.com/images/keyboards/
Virtual-keyboardlg.jpg.
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Virtual Laser Keyboard
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Pointing and Selecting Devices
TB-6
 Alternative pointing devices:
 Graphics tablet
 Eye-tracking device
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Entering Batch Data
TB-7
 Used for repetitive information
 Scanners
Text recognition
software
 RFID technology


Other scanning
technologies

Smart cards
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Specialized Scanning Technologies
TB-8
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Entering Audio and Video
TB-9
 Audio and video input needs to be digitized
 Voice Input
 Microphone
Speech recognition
 Voice-to-text software
 Interactive voice response (IVR)

 Other Forms of Audio Input
 Electronic keyboards
 Transfer from other devices
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Video Input
TB-10
 Digital cameras
 Digital still cameras
 Digital video (DV) cameras
 Streaming video

Compressed form of video that can be sent over the Internet
 Streaming media
 Streaming video with sound
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Processing: Transforming Inputs into Outputs
TB-11
 Binary Codes

Binary or base-2 math (2, 4, 8, 16, 32, etc.)
Bits
 Bytes



Machine language—the language computers understand
ASCII (American Standard Code for Information Interchange)
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System Unit
TB-12
 Houses the computer’s components
 Motherboard, power supply, and fan
 Central processing unit (CPU)
 RAM and ROM memory
 Hard drive
 Optical drives
 Ports
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Clock Speed
TB-13
 Pulses—setting the pace for processing events
 Clock tick: single pulse
 Clock speed is measured in hertz (Hz)
 Personal computer clock speeds:
 First IBM PC was 4.77 MHz
 Today, 3-4 GHz
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Primary Storage
TB-14
 Temporary storage to support computer processing
 Random-access memory (RAM)
 Registers
 Cache memory
 Storage for most recently or most frequently used data
Internal cache—incorporated into the CPU (L1)
 External (or secondary) cache—located close to the CPU (L2)

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Secondary Storage
TB-15
 Hard Drives





Several magnetic disks
Read/write heads
High storage capacity
RAID
Head crash
Source: Pfafffenberger/CIYF Brief 2003,
Prentice Hall, 2003
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Removable Storage Media
TB-16
 Diskettes
 Optical disks
 Use laser beam technology to read and write
 CD-ROMs (compact disc-read-only memory)
 CD-R
(compact disc-recordable)
 CD-RW (compact disc rewritable)

DVD-ROM (digital versatile disk-read-only memory)
 Shorter-wavelength
laser beam
 Digital
Video Disks
 Blu-Ray
 Magnetic tape
 Characters per inch
 Bytes per inch
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Ports
TB-17
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Output Devices: Video Output
TB-18
 Used to display information from a computer
 Cathode Ray Tube (CRT)
 Liquid Crystal Display (LCD)
 Organic Light-Emitting Diodes (OLED)
 Projectors
 Electronic paper (e-paper)

E.g., Amazon Kindle
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Five Generations of Computing
TB-19
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Supercomputers
TB-20
 Most powerful




computers
Processing speed
measured in flops
Typical use: Scientific
research
Numerous processors
working in parallel
Designed to run one
application at a time
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Mainframes
TB-21
 Used in organizational
computing
 Focus on reliability and
input/output speed
 Designed to support
hundreds or thousands of
users concurrently
Source: Courtesy of IBM Corporate
Archives
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Midrange Computers
TB-22
 Used in smaller to midsized organizations
 Support 5-500 users
 Distinction between midrange computers and small
mainframes has blurred
 Microcomputers absorbed functionality once
required by midrange computers
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Microcomputers or PCs
TB-23
 Used by knowledge
workers within
organizations
 More microcomputers
sold than TVs
 Users: 1
 Can also be used as
design workstations or
servers
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Network Computers
TB-24
 AKA thin clients
 Minimal memory and
storage
 Servers do the processing
 Reduce obsolescence &
maintenance
Source: Chris LaGrand/Getty Images, Inc.
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Portable Computers
TB-25
 Notebook computers




Light weight
Battery powered
Limited expandability
Docking stations
 Ultramobile PCs


Subnotebooks
Netbooks
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Tablet PCs
TB-26
 Type of notebook that accepts input from an electronic
pen


Slate model
Convertible model
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Handheld Computers
TB-27
 Small computers that
can be carried in a
pocket
 Niche in the portable
computers market


Personal digital assistants
(PDAs)
Cell phones
 Most popular
manufacturers


RIM—Blackberry
Palm—Treo
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Trade-Offs between Desktop and Portable Computers
TB-28
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Learning Objectives
TB-29
1. Discuss advanced information systems hardware
concepts.
2. Describe advanced topics related to systems and
application software, as well as the characteristics of various
types of programming languages and application
development environments.
3. Describe network software and hardware,
including media access control, network topologies,
and protocols, as well as advanced Internet concepts.
4.
Explain advanced database management
concepts.
IS Today (Valacich & Schneider)
3/27/2017
Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall
Common Task of an Operating System (OS)
TB-30







Booting (or starting) your computer
Reading / Managing programs in memory
Managing file location
Maintaining directory structures
Formatting disks
Controlling the computer monitor
Sending documents to the printer
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Common Operating Systems
TB-31
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Common Types of Computer Software Utilities
TB-32
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Examples of Productivity Software
TB-33
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Open-Source Software
TB-34
 The source code is freely available to the general
public for modification and/or use.
 Many large companies involved in this effort


IBM contributes to the further development of Linux OS
Sun Microsystems develops and extends OpenOffice
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Examples of Open-Source Software
TB-35
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Programming Languages
TB-36
 Used to write application programs
 Examples:
 BASIC
 C/C++
 COBOL
 HTML
 Java
 Program code must be translated into machine
language
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Compilers and Interpreters
TB-37
 Software designed to translate programming
languages into machine code
 Compilers—convert entire program source code at
once
 Programs are compiled before being sold to
customers
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Interpreters
TB-38
 Interpreter—reads, translates, and executes one line of
source code at a time during operation
 Each statement is converted and executed “on the fly”
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Programming Languages
TB-39
 Generations of Programming Languages
 1GL (1940s)—machine language (binary)
 2GL (1950s)—symbolic languages
 3GL (Mid-1950s)—English-like words
 4GL (1970s)—outcome oriented
 5GL—natural languages
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Fourth-Generation Languages
TB-40
 Outcome-oriented language
 Example: SQL
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Fifth-Generation Languages
TB-41
 Called natural languages
 Communication in true English
 Used with artificial intelligence (AI) applications
 Example:
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Object-Oriented Languages
TB-42
 High-level programming languages
 Key features:
 Classes
 Encapsulation
 Inheritance
 Event-driven
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Visual Languages
TB-43
 Visual Languages
 Designed
for
programming
applications that
will have a GUI
Source: Hoffer, George, and Valacich,
Modern Systems Analysis and
Design, 5th ed. (Upper Saddle River,
NJ: Prentice Hall, 2008)
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Web Development Languages
TB-44
 Hypertext Markup Language (HTML)
 Specifies format of Web pages
 Uses tags
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HTML Example
TB-45
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Java and Microsoft.NET
TB-46
 Java
 Developed by Sun Microsystems in early 1990s
 Used for dynamic content
 Applets
 Microsoft.NET
 Can be used on a variety of platforms and devices
 Family of languages
C#
 VB.NET

 Scripting languages
 Created interactivity on Web pages (i.e. JavaScript)
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Automated Development Environments
TB-47
 Computer-aided software engineering
(CASE)
 Used
to design and implement systems
 Automate activities throughout systems
development process
 Examples:
 Reduces
design screen prototypes, generate code
errors
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Example: Use of Case Tools
TB-48
 High-level system design diagram
Source: Hoffer, George, and
Valacich, Modern Systems Analysis
and Design, 5th ed. (Upper Saddle
River, NJ: Prentice Hal, 2008).
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General Types of CASE Tools
TB-49
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Learning Objectives
TB-50
1. Discuss advanced information systems hardware
concepts.
2. Describe advanced topics related to systems and
application software, as well as the characteristics of various
types of programming languages and application
development environments.
3. Describe network software and hardware,
including media access control, network topologies,
and protocols, as well as advanced Internet concepts.
4.
Explain advanced database management
concepts.
IS Today (Valacich & Schneider)
3/27/2017
Copyright © 2010 Pearson Education, Inc. Published as Prentice Hall
Evolution of Computer Networking
TB-51
 Centralized computing
 1940s–1970s (mainframe era)
 Central computer
(mainframe)

Processing and storage of data
 Terminal
 Local input/output device
 Not a true network—no information sharing
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Evolution of Computer Networking (cont’d)
TB-52
 Distributed
Computing




1980s
Driver: Introduction of
PCs
Separate computers
work on subsets of
tasks
Results are shared via
network
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Evolution of Computer Networking (cont’d)
TB-53
 Collaborative Computing
 1990s
 Synergistic form of distributed computing
 Two or more computers working on a common processing task

Computers collaborate to keep employee records current
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Evolution of Computer Networking (cont’d)
TB-54
 Collaborative Computing (cont’d)

Collaborative functionality in IM platforms

Collaborative components in office automation
applications

E.g., SharePoint
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Types of Networks
TB-55
 Private Branch
Exchange (PBX)
 Telephone system
serving a particular
location
Connects phones and
computers
 Connects PBX to
outside network

 Limited bandwidth
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Types of Networks (cont’d)
TB-56
 Local Area Network
 Spans relatively small area—tens of kilometers
 Computers share:
 Information
 Peripheral devices
 Usually one type
of cable used
 Wireless Local
Area Network
(WLAN)
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Types of Networks (cont’d)
TB-57
 Campus area network
 Spans multiple buildings
 Wide Area Network
 Spans relatively large area
Usually connects multiple LANs
 Different hardware and transmission media used
 Used by multinational companies



Information transmitted across cities and countries
Four specific types of WANs
Metropolitan area networks
 Enterprise networks
 Value-added networks
 Global networks

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Types of Networks (cont’d)
TB-58
 Metropolitan area networks
 Usually in cities
 Enterprise networks
 Connect disparate networks
of a single organization
 Value-added networks
(VANS)

Managed by third parties
 Global networks
 Span multiple countries
 Example: The Internet
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Types of Networks (cont’d)
TB-59
 Personal Area Networks
 Exchange data between
computing devices
 Short range radio
communication—
10 meters


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Examples: networking
of PCs, peripheral
devices, mobile phones,
portable stereos, etc.
Enabling Technology:
Bluetooth
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Network Services
TB-60
 File services

Store, retrieve, and move
data files
 Print services

Control and manage
access to printers
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Network Services (cont’d)
TB-61
 Message services
 Store, access, and deliver data
 Communication between users
and applications
 Application services
 Run software for network clients
 Enable computers to share
processing power
 Client/server computing
 Network operating system
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Cable Media
TB-62
a) Several twisted pairs
b) Sample network installation
Sources: (a) © Belkin Components; (b) © Getty Images, Inc.
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Coaxial Cable
TB-63
 Components
 Solid inner copper
conductor
 Plastic insulation
 Outer braided copper or
foil shield
Source: © Getty Images, Inc.
 Variety of thicknesses
 Thinnet—less costly than TP but not commonly used
 Thicknet—more costly than TP

Used for cable television and networks operating at 10-100 Mbps
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Fiber-Optic Cable
TB-64
 Components:
 Light-conducting glass or plastic
 Cladding (glass)
 Tough outer sheath
 Transmission:
 Pulses of light
 Immune to EMI and eavesdropping
 Low attenuation
 100 Mbps to more than 2 Gbps
 Distance: up to 25 kilometers
 Used for high-speed backbones
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Source: © Getty Images, Inc.
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Wireless Media: Infrared Line of Sight
TB-65





High frequency light waves
Distance of up to 24.4 meters
Attenuation, EMI and eavesdropping problems
Relatively inexpensive
Two types:

Point-to-point
Strict line of sight
 Up to 16 Mbps at 1 meter
 Example: TV remote


Broadcast
No need for direct line of sight
 Less than 1 Mbps

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Wireless Media: High Frequency Radio
TB-66
 Ideal for mobile transmission
 Expensive due to cost of antenna towers
 Complex installation
 Susceptible to EMI and eavesdropping
 Attenuation not a problem
 Distance between nodes 12.2–40 kilometers
 Rate up to several hundred Mbps
 Examples: cellular phones and wireless networks
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Cellular Network
TB-67
 Coverage area divided into cells
 Low-powered radio antenna/receiver
 Cells controlled by a central computer
 Unique frequency assigned for duration of phone
call
 Mostly digital today
Less static
 Data transmission
capability
 Wider reception range

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Evolution of the Cell Phone Technology
TB-68
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Wireless Media: Microwave
TB-69
 High-frequency radio
 Terrestrial microwave
Line-of-sight
 Transmission up to 274 Mbps
 EMI and eavesdropping problems
 Cross inaccessible terrain
 Cost depends on distance
 Alternative when cabling too
expensive

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Microwave (II): Satellite Microwave
TB-70
 Relay station transfers signals between antennae on earth
and satellites in the orbit





Propagation delay
Satellites orbit 400-22,300 miles
above earth
Typically 1-10 Mbps, up to 90 Mbps
Prone to attenuation
Susceptible to EMI and
eavesdropping
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Characteristics of Satellites with Different Orbits
TB-71
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Relative Comparison of Wireless Media
TB-72
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Network Software and Hardware
TB-73
 Standards ensure interpretability and
compatibility of network devices
 Established by IEEE
 Three major standards for LANs
 Software blended with hardware to implement
protocols
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Media Access Control
TB-74
 Problem: Collision occurs when 2 workstations
transmit data simultaneously
 Media Access Control: Set of rules that govern
access
 Types of Media Access Control:

Distributed
1 workstation at a time with access
 Authorization transferred sequentially


Random access
Any workstation can transmit if medium is available
 No permission required

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Distributed Access Control
TB-75
 Token passing most
common
Uses electronic token—
small packet of data
 Only computers
possessing token can
send—avoids collisions

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Random Access Control
TB-76

•
•
CSMA/CD—Carrier Sense Multiple
Access/Collision Detect
Most commonly used method of random access
Workstation listens
1. If network is quiet, workstation transmits
2. Message sent to all workstations on the network
3. Destination with proper address opens the message

Collisions more likely under heavy traffic
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Network Topologies: Star
TB-77
 All workstations




connected to a central hub
Active hubs amplify
transmission
Easy to lay out and modify
Most costly (cabling)
Failure of hub can cause
network failure
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Network Topologies: Ring
TB-78
 Messages move in one
direction around the
circle
 Covers large distances
 Relatively little cabling
 Failure of one node can
cause network failure

Self-healing ring
 Difficult to modify
 Token passing used
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Network Topologies: Bus
TB-79
 Open-ended line
 Easiest to extend
 Simplest wiring layout
 All nodes can receive
the same message at
the same time
 Difficult to diagnose
network faults
 Uses CSMA/CD
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Network Topologies: Mesh
TB-80
 Devices fully or partially
connected to each other


Full mesh
Partial mesh
 Short routes between
nodes
 Many possible routes
 Performs well in heavy
traffic
 Most WANs use partial
mesh
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The Open System Interconnection (OSI) Model
TB-81
 Open System Interconnection (OSI)
 Seven layers
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OSI Model: Message Transmission
TB-82
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Ethernet
TB-83
 LAN protocol developed by Xerox in 1976
 Bus network topology
 Random access control
 Originally: 10 Mbps
 Later: 100Base-T (Fast Ethernet)—100 Mbps
 Latest: Gigabit Ethernet—1,000 Mbps
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Connectivity Hardware
TB-84
 Network interface card
 Connectors
 Computers use digital signals
 Phone lines can only handle analog signals
 Modems
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Modems
TB-85
 Enable transmission over telephone lines
 Digital signal converted to analog
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Networking Hardware
TB-86
 Repeaters—replicate signal
 Hubs—central point of connection
 Bridges—connect two different LANs
 Multiplexers—used to share communication lines
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Networking Hardware (cont’d))
TB-87
 Routers—connect 2 or more individual networks
 Brouters—capabilities of bridge and router
 Channel service unit—buffer between LAN and
public carrier’s WAN
 Gateway—performs protocol conversion
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Connecting Independent Networks
TB-88
 Routers interconnect independent networks
 Fundamental building blocks of Internet
 Router:
 Special-purpose
computer
 Only jobs:
Interconnect
networks
 Forward data
packets

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Backbone Networks
TB-89
 Manage bulk of network traffic, high speed
Source: Douglas E. Comer, The
Internet Book, 2nd ed. (Upper
Saddle River, NJ: Prentice Hall,
1997)
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Who Manages the Internet?
TB-90
 National and international committees
 Coordinating Committee for Intercontinental
Research Networks
 The Internet Society
Over 150 organizational members
 16,000 individual members
 Internet Engineering Task Force
 Internet Architecture Board (IAB)

 Groups help manage Internet standards
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Internet Registry
TB-91
 Central repository for Internet-related information
 Central maintenance of Domain Name System (DNS)
Match domain names with IP addresses
 www.apple.com = 17.251.200.32

 Starting in 1993, InterNIC managed directory and
database services
 Late 1990s—Internet Corporation for Assigned Names
and Numbers (ICANN): manages IP addresses,
domain names and root server system
 IPv6 created to meet growing demand for Internet
addresses
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How to Connect to the Internet
TB-92
 Internet service provider (ISP)
 ISPs connect to each other through Network access
points (NAPs)
Determine how
traffic is routed
 Key component of
the Internet backbone
 Hierarchical structure

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Methods for Connecting to the Internet
TB-93
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Business Internet Connectivity
TB-94
 Increased needs for bandwidth
 High-speed options
 T1 Lines


T3 Lines


1.544 Mbps
45 Mbps
Asynchronous transfer mode (ATM)
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Capacity of Telecommunication Lines
TB5-95
 OC—Optical Carrier
 Synchronous optical network standard (SONET)
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Asynchronous Transfer Mode (ATM)
TB-96
 Transmission of voice, video, and data
 Up to 2.2 Gbps
 Used for LANs and WANs
 Integration of disparate networks
 Packet-switched transmission
 Fixed-length cells (53 bytes)
 Can be used without routers
 Especially interesting for movie and entertainment
industries
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The Future of Connectivity
TB-97
 New innovations
 Broadband over power lines
Power line communication
 Use of power distribution wires
 Current rates: 1 Mbps
 Infrastructure readily available


WiMax
“Last mile” wireless
 High-speed stationary wireless
 Does not require line-of-sight
 Currently expensive

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Current State of Internet Usage
TB-98
 The most prominent global network
 1 billion people
 15 percent of world’s population have access at home
 290 percent increase since 2000
 Asia—most users
 North America—largest percentage of population are
users (73.1 percent)
 Africa—smallest percentage (5.3 percent)

Rapid growth—1030 percent
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Growth in Internet Servers (Hosts)
TB-99
Source: Internet Systems Consortium. http://www.isc.org/index.pl?/ops/ds/host-counthistory.php.
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Learning Objectives
TB-100
1. Discuss advanced information systems hardware
concepts.
2. Describe advanced topics related to systems and
application software, as well as the characteristics of various
types of programming languages and application
development environments.
3. Describe network software and hardware,
including media access control, network topologies,
and protocols, as well as advanced Internet concepts.
4.
Explain advanced database management
concepts.
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Database Design
TB-101
 Poor data model will result in data that are
 Inaccurate
 Redundant
 Difficult to search
 Poorly designed database is difficult to maintain
and process
 Entities have attributes

Each instance of an entity must have a unique identifier
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Example: Entities and Their Attributes
TB-102
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Identifying Records
TB-103
 Uniquely identifying records:
 Primary Key
Unique identifier
 Examples: Student ID number, social security number


Combination primary key
Combination of two or more attributes
 Example: Identifying a student’s grade for a particular class for a
particular term

 Identifying records that share a common value
 Secondary Key
Attribute not used as a primary key
 Example: Major

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Associations (Relationships)
TB-104
 Used to relate information between tables
 Needed to retrieve information
 Example: Basketball league database
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Example: Basketball League
TB-105
 Each table contains
important data
 No way to learn which
team plays in a specific
stadium
 Need to make
associations
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Example: Basketball League
TB3-106
 Foreign keys
 Attributes used to link tables
 Primary key in one table, foreign key in another
 Need to create additional entity for many-to-many relationships
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Entity-Relationship Diagram
TB-107
 Used to show associations between entities
 Important when designing complex databases
 Entities: represented by boxes
 Relationships: represented by lines
Associations
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The Relational Model
TB-108
 Primary DBMS
approach (RDBMS)
 3 dimensions

Entities represented
as 2-dimensional tables
Rows = records
 Columns = attributes


Tables joined based
on common columns
(3rd dimension)
 Good design eliminates
redundancy
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Data Redundancy
TB-109
 Problematic if an attribute has to be changed
 Need to change in multiple locations

Example: instructor’s phone number
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Normalization
TB-110
 Eliminate unnecessary
redundancy
Create separate
tables
 Data only
needs to be
changed
in a single
location

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