Technology in Action Alan Evans Kendall Martin Mary

Technology in Action Alan Evans • Kendall Martin Mary Anne Poatsy Ninth Edition Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

Technology in Action Final Review Chapters 8 -13 Copyright © 2010 Pearson Education, Inc. Publishing as Prentice Hall 2

Technology in Action Chapter 8 Digital Lifestyle: Managing Digital Data and Devices Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

How Cellular Works • • • Sound enters microphone as sound wave Analog-to-digital converter chip converts voice sound waves into digital signals Digital signal processor compresses the signal so it will transmit more quickly Digital signal processor decompresses incoming message Amplifier boosts signal to make it louder and passes it to speaker Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 4

Cell/Smartphone Processors • Processor coordinates sending all data among other electronic components • Runs the cell/smartphone’s operating system which provides user interface • Popular processors include: – Qualcomm Snapdragon – Apple A 4 – Marvel XScale Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 5

Cell/Smartphone Operating Systems • Each manufacturer makes own small changes and designs own user interface • Number of operating systems available – Windows Phone 7 – Apple’s i. OS for i. Phone – web. OS for HP Pre – Android by Google – Open source systems Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 6

Text Messaging • Short message service (SMS) – Allows you to send short text messages – Up to 160 characters – Convenient and quicker than e-mail • SMS uses cell phone network to send messages to any SMS device in world • MMS is an extension that allows you to send messages that include, text, sound, images, and video Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 7

Chapter 8 Summary Questions 4. How is digital media different from analog? Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 8

Technology in Action Chapter 9 Securing Your System: Protecting Your Digital Data and Devices Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 9

What Viruses Do • Main purpose – Replicate themselves and copy code to as many other files as possible • Secondary objectives – Slow down networks – Display annoying messages – Destroy files or contents of hard drive Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 10

Catching a Virus • If exposed to an infected file, the virus will try to copy itself and infect a file on your computer • Sources of virus infection – Downloading infected audio and video files – Shared flash drives – Downloading or executing a file attached to e-mail Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 11

Computer Safeguard: Antivirus Software and Software Updates • Antivirus software is designed to detect viruses and protect your computer • Popular antivirus software companies – Symantec – Kaspersky – AVG – Mc. Afee • Comprehensive Internet security packages protect you from other threats Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 12

Antivirus Software • Designed to detect suspicious activity – Scan files for virus signatures (unique code) – Identifies infected files and type of virus – Provides choice of deleting or repairing infected file – Places virus in secure area (quarantining) – Records key attributes about file and rechecks these statistics during scan (inoculating) Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 13

Denial-of-Service Attacks • In a denial-of-service (Do. S) attack, users are denied access to computer system because hacker is making repeated requests • When flooded with requests, the system shuts down • Distributed denial-of-service (DDo. S) attack launches attacks from more than one zombie computer Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 14

Firewalls • Software program or hardware designed to protect computers from hackers – Consider installing both for maximum protection • Software firewalls – Most operating systems include firewall – Many security suites include firewall software • Hardware firewall devices – Routers – Keep unused logical ports closed Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 15

Malware, Adware, and Spyware • Malware – Software that has malicious intent • Adware – Displays sponsored advertisements – Pop-up windows • Spyware – Unwanted piggyback programs that download with other software you install from Internet that transmit information about you Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 16

Spam • Unwanted or junk e-mail • Avoid spam in primary e-mail account – Create free Web-based e-mail account – Use spam filter – Read privacy policy – Don’t reply to spam to remove yourself from list – Subscribe to e-mail forwarding service Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 17

Cookies • Small text files that Web sites automatically store on hard drive to make return visit more efficient and better geared to your interests • Web site assigns ID number to computer • Provide Web sites with information about browsing habits • Some sites sell information cookies collect • Not a security threat Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 18

Phishing and Pharming • Phishing lures users to reveal personal information that could lead to identity theft – E-mail messages look legitimate • Pharming is when malicious code is planted on your computer – Alters browser’s ability to find Web addresses – Directed to bogus Web sites that gather personal information Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 19

Scareware • Type of malware downloaded onto computer that tries to convince you that computer is infected with virus • Then directed to site to buy fake removal tools Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 20

Chapter 9 Summary Questions 5. What is a firewall, and how does it keep my computer safe from hackers? Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 21

Chapter 9 Summary Questions 11. How do I protect my physical computing assets from environmental hazards, power surges, and theft? Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 22

Technology in Action Chapter 10 Behind the Scenes: Software Programming Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

Analysis • Analysts explore problem to be solved • Develop program specifications – Clear statement of goals and objectives of project • Feasibility assessment is performed • User requirements are defined • Analysts recommend a plan of action Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 24

Describing the Problem • The Problem Statement – Staring point of programming work – Clear description of tasks the computer program must accomplish – How the program will execute these tasks – How the program will respond to unusual situations Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 25

Design • A detailed plan for programmers is developed • Flowcharts and data-flow diagrams are used for the current and proposed system Data-flow diagram Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 26

Program Development Life Cycle Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 27

Step 1: Describing the Problem • Programmers develop a complete description of problem • Problem statement identifies task to be automated • Statement describes how software will behave Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 28

Step 2: Making a Plan • Problem statement is translated into a set of specific, sequential steps known as an algorithm • Algorithm is written in natural ordinary language such as English Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 29

Step 3: Coding • Algorithm is translated into programming code • Programmers must think in terms of operations that a CPU can perform Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 30

Step 4: Debugging • Code goes through process of debugging • Programmers repair any errors found in code Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 31

Step 5: Finishing the Project • Software is tested – Programming team – People who will use program • Results of entire project are documented • Users are trained to use program efficiently Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 32

Flowchart Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 33

Pseudocode Bold terms show actions that are common in programming, such as reading data, making decisions, printing, and so on. 1. Ask the user how many hours they worked today 2. If the number of hours worked < = 8, compute total pay without overtime otherwise, compute total pay with overtime pay 3. Print total pay Underlined words are information items that appear repeatedly in the algorithm. Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 34

Visual Basic 2010 • Visual Basic 2010 is the current version • Builds object-oriented applications for: – Windows – The Web – Mobile Devices • Easy to drag and drop entire programming components into application Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 35

C and C++ • C – Developed for system programmers – Provides higher-level programming features • if statements and for loops • C++ – Uses same symbols and keywords as C – Better security – Support for reuse of existing code – Includes object-oriented design Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 36

Java and C# • Java – Object-oriented features – Large set of existing classes – Architecture neutral – Java applets: Small Java-based programs • C# – Completing program released by Microsoft Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 37

Objective C • Language most often used to program applications to run under Mac OS X – Object-oriented language – Superset of the C language – Often used with library called Cocoa Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 38

Scripting Languages for the Web • Simple programming language limited to performing a set of specialized tasks • Scripts allow decisions to be made and calculations to be performed • Java. Script, VBScript, and PHP work well with HTML Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 39

ASP, JSP, and PHP • Used by programmers to build Web sites with interactive capabilities • User supplies information that is translated into a request. • Scripting code controls automatic writing of the custom page returned to user’s computer Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 40

Flash and XML • Adobe Flash – Used to develop Web-based multimedia – Includes its own scripting language, Action. Script • XML (e. Xtensible Markup Language) – Enables designers to define data-based tags – Makes it easier for Web site to transfer key information on its page to another site Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 41

AJAX • Asynchronous Java. Script And XML – Allows creation of Web applications that can update information without requiring a page refresh – Uses existing technologies to do more processing in the browser – Users have a more responsive experience Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 42

Technology in Action Chapter 11 Behind the Scenes: Databases and Information Systems Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

Life Without Databases • Not every situation demands complexity of a database • For simple tasks, lists are adequate – Table created in Microsoft Word – Spreadsheet created in Microsoft Excel • Lists are not appropriate for complex information Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 44

Advantages of Using Databases • Databases store and retrieve large quantities of information easily • Provide information in seconds • Three main advantages: – Enable information sharing – Promote data integrity – Allow flexible use of data Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 45

Database Terminology • Databases have three main components; – Fields • Store each category of information • Displayed in columns – Records • Group of related fields – Tables (or files) • Group of related records Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 46

Fields, Records, and Tables Table containing student’s contact information Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 47

Common Data Types Data Type Used to Store Examples Text Alphabetic or alphanumeric data Cecelia PSY 101 Numeric Numbers 512 1. 789 Calculated Computational formula Credit hours x per-credit tuition charges Dates in standard notation 2/21/2016 Memo Long blocks of text I have a dream that one day this nation will rise up and live out … Object Multimedia files or document MP 3 file AVI file Hyperlink to a Web page www. pearson highered. com Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 48

Primary Keys • Each record must have one field that has a value unique to that record • Unique field is called a primary key – Student ID numbers – Social Security numbers – Driver’s license numbers – Unique order numbers Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 49

Relational Databases • Organize data in table format • Logically group similar data into a relation (a table that contains related data) • Each record is assigned primary key • Tables are linked to each other through their primary keys Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 50

Creating Databases & Entering Data • First define data to be captured • Data dictionary or database schema – Defines name, data type, and length of each field Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 51

Query Languages • Modern databases contain a query language used to retrieve and display records • Most popular is Structured Query Language, or SQL • Wizards speed up process of creating queries Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 52

Types of Relationships • One-to-one – For each record in a table, there is only one corresponding record in a related table • One-to-many – Only one instance of a record in one table; many instances in a related table • Many-to-many – Records in one table related to multiple records in another Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 53

Data Warehouses • Large-scale electronic repository of data • Organizes in one place all the data related to an organization • Consolidate information • Data organized by subject Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 54

Populating Data Warehouses • Source data can come from three places: – Internal sources • Company databases, etc. – External sources • Suppliers, vendors, etc. – Customers or visitors to company’s Web site • Clickstream data Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 55

Data Marts • Looking for data in a data warehouse can be daunting • Small slices of data warehouse, called a data mart are often created • Data warehouses have an enterprisewide depth • Data marts may pertain to a single department Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 56

Transaction-Processing Systems A TPS keeps track of everyday business activities • Batch processing – data is accumulated and several transactions are processed at once • Real-time processing – database is queried and updated while transaction takes place Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 57

Decision Support Systems • A DSS helps managers develop solutions for specific problems – Uses data from databases and data warehouses – Enables users to add own insights and experiences and apply them to the solution Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 58

Technology in Action Chapter 12 Behind the Scenes: Networking and Security in the Business World Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

Client/Server Networks • Client/server networks contain servers as well as client computers • Server is computer that stores and shares resources on a network • Client is computer that requests those resources • Servers respond to requests from large number of clients Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 60

Classifications of Client/Server Networks • Networks are classified according to size and distance between physical parts • Four popular classifications: – Local area networks (LANs) – Wide area networks (WANs) – Metropolitan area networks (MANs) – Personal area networks (PANs) Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 61

Other Networks • Intranet – Private network of business or organization – Not accessible by unauthorized individuals • Extranet – An area of an intranet that only certain corporations or individuals can access – Useful for enabling electronic data interchange Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 62

Servers • • • Workhorses of the client/server network Interface with many network users Assist with a variety of task Small networks have just one server Large networks use dedicated servers – Fulfill one specific functions – Reduce load on main server Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 63

Network Topologies • Arrangement of computers, transmission media, and other network components • Physical topology – Layout of “real” components of network • Logical topology – Virtual connections among network nodes • Protocol is set of rules for exchanging communication Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 64

Bus Topology • All computers are connected in sequence on a single cable • Used in peer-to-peer networks Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 65

Ring Topology • Nodes are laid out in a ring • A token (data packet) flows in one direction from device to device • Recent versions have data transfer rates of up to 100 Mbps Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 66

Star Topology • Most widely deployed client/server network layout • Nodes connect to a central communications device (switch) • Switch receives a signal and retransmits it • A node accepts only signals addressed to it Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 67

Twisted-Pair Cable • Pairs of copper wire twisted around each other • Twists make the wires less susceptible to outside interference • Two types • Shielded twisted-pair (STP) • Unshielded twistedpair (UTP Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 68

Coaxial Cable • Four main components – Copper core – Nonconductive insulating material – Braided metal shielding – Plastic cover Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 69

Fiber-Optic Cable • Components include – Glass or plastic fibers – Cladding – Outer jacket • Transmission in only one direction • Signals converted to light pulses • Immune to interference Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 70

Wireless Media Options • Usually add-ons that extend access to wired network • Often provided to give employees a wider working area • Corporate networks are often a combination of wired and wireless media Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 71

Comparing Transmission Media Cable Characteristics Twisted Pair (Cat 6) Twisted Pair (Cat 6 a) Fiber-Optic Maximum run length 328 feet (100 m) Up to 62 miles (100 km) Bandwidth Up to 1 Gbps Up to 10 Gbps 10 to 40 Gbps Bend radius (flexibility) No limit 30 degrees/foot Cable cost Extremely low Low High Installation cost Extremely low Most expensive because of installation training required Susceptibility to interference High None (not susceptible to EMI or RFI) Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 72

Switches and Bridges • Used to send data on a specific route through network • Switch makes decisions based on MAC address as to where data is sent • Bridge is a device used to send data between different collision domains Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 73

Routers • Router is designed to send information between two networks • Must look at higher-level network addresses such as IP addresses Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 74

Technology in Action Chapter 13 Behind the Scenes: How the Internet Works Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall

Management of the Internet • No single entity is in charge of Internet • Local networks are owned by: – Individuals – Universities – Government agencies – Private companies • Managed by nonprofit organizations and user groups Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 76

Connecting to the Internet • Internet backbone – Collection of large national and international networks – T lines: Initially used for backbone ISP connections • Carried digital data over twisted-pair wires – Optical carrier line (OC): Today’s most common backbone ISP connection • High-speed, fiber-optic lines designed to provide high throughput Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 77

Types of Servers • Web servers – Host Web pages • Commerce servers – Enable the purchase of goods and services over the Web • File servers – Provide remote storage space for files that users can download Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 78

Circuit Switching • Technology available in 1960 s • Dedicated connection is formed between two points • Remains active for duration of transmission • Used since early days of the telephone communications • Inefficient for computers Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 79

Packet Switching • Makes computer communication efficient • Data is broken into small units (packets) • Packets are sent over various routes to their destination • Packets are reassembled by the receiving computer Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 80

TCP/IP • Main suite of protocols used on Internet • Transmission Control Protocol (TCP) – Prepares data for transmission – Provides error checking – Enables resending lost data • Internet Protocol (IP) – Responsible for sending information from one computer to another Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 81

IP Address • Unique number that identifies each device connected to the Internet • Typical IP address – 197. 24. 72. 157 • Static addressing – IP Address never changes • Dynamic addressing – Temporary address from available pool Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 82

Domain Names • Domain name takes place of an IP address • Easier to remember • Organized by level – Top-level domain (TLD) • Portion of the domain name that follows the dot • Includes. com, . org, . gov, . edu, and. net – Second-level domain • Unique name within a top-level domain • Yahoo. com, Whitehouse. gov, Unesco. org Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 83

Domain Name System Servers • Internet servers that translate domain names into IP addresses • ISPs go first to a default DNS to resolve a name • Name queries work up the hierarchy to the root DNS servers if required Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 84

Web Browser Security Protocols • Hyper. Text Transfer Protocol (HTTP) – For transfer of hypertext documents • Hyper. Text Transfer Protocol Secure (HTTPS) – Combination of HTTP and network security protocol • Transport Layer Security (TLS) and Secure Sockets Layer (SSL) – Protect data integrity of data and security of transmissions over the Internet Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 85

Client Side Applications • Programs that run on client computer with no interaction with a Web server • Two main types: – Embedding programming language code directly within HTML or XHTML code of a Web page – Applet is a small application that resides on a server and when requested, compiled version is downloaded to client computer Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 86

Communications over the Internet • Communications revolution began to explode in the mid 1990 s • Internet e-mail – Growing exponentially each month – 97 percent is spam • Texting and instant messaging • Voice over Internet protocol Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 87

E-Mail • Simple Mail Transfer Protocol (SMTP) is used for sending e-mail along Internet • Popular client-based e-mail software: – Microsoft Outlook – Mozilla Thunderbird • Web-based e-mail software – Gmail – Yahoo! – Hotmail Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 88

E-Mail (cont. ) • Multipurpose Internet Mail Extensions (MIME) simplifies attachments to e-mail messages • Handles encoding and decoding Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 89

Instant Messaging • Act of communicating with one or more people in real time • Top IM programs – AOL Instant Messenger (AIM) – Google. Talk – Yahoo! Messenger – Jabber – Windows Live Messenger Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 90

Voice over Internet Protocol (Vo. IP) • Turns standard Internet connection into way to make free long-distance phone calls • Collection of communication and transmission protocols • Uses TCT/IP protocols to route phone calls across the Internet Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 91

Chapter 13 Summary Questions 1. Who owns, manages, and pays for the Internet? Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 92

Chapter 13 Summary Questions 3. What data transmissions and protocols does the Internet use? Copyright © 2013 Pearson Education, Inc. Publishing as Prentice Hall 93