1. CSCI-235 Micro-Computer Applications Privacy & Security I

2. © Prentice-Hall, Inc Privacy in Cyberspace  Privacy refers to an individual’s ability to restrict the collection, use, and sale of confidential personal information  The Internet is eroding privacy through the selling of information collected through Web sites  Few laws regulate selling personal information

3. © Prentice-Hall, Inc Cookies  Cookies are small files that are written to an individual’s hard drive whenever a Web site is visited  Legitimate purposes of cookies include recording information for future use. Example: retail sites using “shopping carts”  Questionable practices include banner ad companies tracking a user’s browsing actions and placing banner ads on Web sites based on those actions

4. © Prentice-Hall, Inc Cookies  A small text file stored on your hard drive  File is sent back to the server each time you visit that site Stores preferences, allowing Web site to be customized Stores preferences, allowing Web site to be customized Stores passwords, allowing you to visit multiple pages within the site without logging in to each one Stores passwords, allowing you to visit multiple pages within the site without logging in to each one Tracks surfing habits, targeting you for specific types of advertisements Tracks surfing habits, targeting you for specific types of advertisements

5. © Prentice-Hall, Inc Example of Cookies

6. © Prentice-Hall, IncSecurity  Hacker – someone who attempts to gain access to computer systems illegally Originally referred to as someone with a high degree of computer expertise Originally referred to as someone with a high degree of computer expertise

7. © Prentice-Hall, Inc Definition of a Hacker  Hacker noun (see Raymond, 1991) A person who enjoys learning the details of computer systems and how to stretch their capabilities – as opposed to the most users of computers, who prefer to learn only the minimum amount necessary A person who enjoys learning the details of computer systems and how to stretch their capabilities – as opposed to the most users of computers, who prefer to learn only the minimum amount necessary One who programs enthusiastically or who enjoys programming rather than just theorizing about programming One who programs enthusiastically or who enjoys programming rather than just theorizing about programming

8. © Prentice-Hall, Inc Definition of a Hacker  Person who is an expert or enthusiastic of any kind is an expert or enthusiastic of any kind enjoys the intellectual challenge of creatively overcoming or circumventing limitations enjoys the intellectual challenge of creatively overcoming or circumventing limitations  Used as a compliment

9. © Prentice-Hall, Inc First Network Hack (Telephone)  John Draper (AKA Cap’n Crunch)  1970’s: Free long distance calls using a whistle found in a cereal box Free long distance calls using a whistle found in a cereal box  Whistle emits the same frequency as AT&T long lines to indicate a line was ready to route a new call (2600 Hz)

10. © Prentice-Hall, Inc First Network Hack (Telephone)  Flaw: AT&T took cost cutting measures AT&T took cost cutting measures The signaling and voice used the same circuit The signaling and voice used the same circuit This flaw made the system vulnerable to anybody that can generate 2600 Hz This flaw made the system vulnerable to anybody that can generate 2600 Hz  Solution: Now signaling takes place on a separate path from the one you talk on Now signaling takes place on a separate path from the one you talk on

11. © Prentice-Hall, Inc Computer Viruses  Computer viruses are malicious programs that infect a computer system causing various problems with its use  Viruses replicate and attach themselves to programs in the system  There are more than 20,000 different computer viruses with the number growing daily

12. © Prentice-Hall, Inc How Virus Infections Spread  Virus Infections spread by: Inserting a disk with an infected program and then starting the program Inserting a disk with an infected program and then starting the program Downloading an infected program from the Internet Downloading an infected program from the Internet Being on a network with an infected computer Being on a network with an infected computer Opening an infected e-mail attachment Opening an infected e-mail attachment

13. © Prentice-Hall, Inc Virus Myths  You cannot get infected by simply being online If you download and execute an infected file, you can get infected If you download and execute an infected file, you can get infected  Although most e-mail viruses (e.g., the Melissa virus) are in attachments that must be opened, it is possible to get infected by viewing an e-mail

14. © Prentice-Hall, Inc Types of Viruses  File Infectors Attach themselves to program files Attach themselves to program files Spread to other programs on the hard drive Spread to other programs on the hard drive Are the most common type of virus Are the most common type of virus  Boot Sector Viruses Attach themselves to the boot sector of a hard drive Attach themselves to the boot sector of a hard drive Execute each time the computer is started Execute each time the computer is started May lead to the destruction of all data May lead to the destruction of all data

15. © Prentice-Hall, Inc More Rogue Programs  Time Bombs Also called logic bombs Also called logic bombs Harmless until a certain event or circumstance activates the program Harmless until a certain event or circumstance activates the program  Worms Resemble a virus Resemble a virus Spread from one computer to another Spread from one computer to another Control infected computers Control infected computers Attack other networked computers Attack other networked computers  Trojan Horses Disguise themselves as useful programs Disguise themselves as useful programs Contain hidden instructions Contain hidden instructions May erase data or cause other damage May erase data or cause other damage

16. © Prentice-Hall, Inc Identity Theft  Identity theft is one of the fastest growing crimes in the United States and Canada  Identity theft occurs when enough information about an individual is obtained to open a credit card account in their name and charge items to that account  Examples of information needed are name, address, social security number, and other personal information  Laws limit liability to $50 for each fraudulent charge  An individual’s credit report is affected by identity theft

17. © Prentice-Hall, Inc Using Firewalls  Firewalls are programs that are designed to prohibit outside sources from accessing the computer system  A personal firewall is designed to protect home computers from unauthorized access while being connected to the Internet

18. © Prentice-Hall, Inc Using Antivirus Programs  They use pattern-matching techniques to examine program files for patterns of virus code  Two drawbacks: They cannot find viruses not in their database They cannot find viruses not in their database They cannot find new viruses that alter themselves to evade detection They cannot find new viruses that alter themselves to evade detection  Use antivirus programs that offer frequent updates and monitor system functions  Check disks that were used on another system for viruses

19. © Prentice-Hall, Inc Backing Up Data  Back up programs and data regularly  Store backups away from the computer system  Types of backups: Full backups – Back up everything stored on the computer once a month Full backups – Back up everything stored on the computer once a month Incremental backups – Daily or weekly back up of only those files that have changed since the last back up Incremental backups – Daily or weekly back up of only those files that have changed since the last back up

20. © Prentice-Hall, Inc The Encryption Debate  Encryption is the coding and scrambling process by which a message is made unreadable except by the intended recipient  Encryption is needed for electronic commerce