Understanding Computers in a Changing Society, 3 rd Edition Chapter 4 Network and Internet Security
Learning Objectives Explain why computer users should be concerned about network and Internet security. List several examples of unauthorized access, unauthorized use, and computer sabotage. Explain how access control systems, firewalls, antivirus software, and encryption protect against unauthorized access, unauthorized use, and computer sabotage. Discuss online theft, identity theft, Internet scams, spoofing, phishing, and other types of dot cons. Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 2
Learning Objectives Detail steps an individual can take to protect against online theft, identity theft, Internet scams, spoofing, phishing, and other types of dot cons. Identify personal safety risks associated with Internet use. List steps individuals can take to safeguard their personal safety when using the Internet. Name several laws related to network and Internet security. Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 3
Overview This chapter covers: Security concerns stemming from the use of computer networks Safeguards and precautions that can be taken to reduce the risk of problems related to these security concerns Personal safety issues related to the Internet Safeguards and precautions that can be taken to reduce the risk of problems related to these personal safety issues Legislation related to network and Internet security Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 4
Why Be Concerned about Network and Internet Security? Security concerns related to computer networks and the Internet abound Computer crime (cybercrime): Any illegal act involving a computer, including: Breaking through the security of a network Theft of financial assets Manipulating data for personal advantage Act of sabotage (releasing a computer virus, shutting down a Web server) All computer users should be aware of security issues and the precautions that can be taken Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 5
Unauthorized Access and Unauthorized Use Unauthorized access: Gaining access to a computer, network, file, or other resource without permission Unauthorized use: Using a computer resource for unapproved activities Both can be committed by insiders and outsiders Codes of conduct: Used to specify rules for behavior, typically by a business or school Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 6
Unauthorized Access and Unauthorized Use Hacking: The act of breaking into another computer system A serious threat for individuals, business, and the country (national security) Wi-Fi hacking: Common for hackers to gain entrance via Wi-Fi War driving or Wi-Fi piggybacking: Using someone else s Wi-Fi network to gain free access to the Internet Illegal in some areas Can lead to criminal behavior Ethical issues Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 7
Unauthorized Access and Unauthorized Use Interception of communications: Gaining unauthorized access to data as it is being sent over the Internet or another network The increased use of wireless networks has opened up new opportunities for data interception Business and personal wireless networks Use of public hotspots Wireless connections with mobile phones and mobile devices Once intercepted, the content can be read, altered, or otherwise used for unintended purposes Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 8
Computer Sabotage Computer sabotage: Acts of malicious destruction to a computer or computer resource Bot: A PC that is controlled by a computer criminal Botnet: A group of bots that can work together in a controlled fashion Used by botherders to send spam, launch Internet attacks and malware, etc. Malware: Any type of malicious software Includes viruses, worms, Trojan horses, etc. Increasingly used for computer crimes and to take control of individuals PCs for botnet activities Can infect mobile phones and mobile devices (some preinstalled on mobile devices) Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 9
Computer Sabotage Computer virus: Malicious program embedded in a file that is designed to cause harm to the computer system Often embedded in downloaded programs and e-mail messages Computer worm: Malicious program designed to spread rapidly by sending copies of itself to other computers Typically sent via e-mail Trojan horse: Malicious program that masquerades as something else Usually appear to be a game or other program Cannot replicate themselves; must be downloaded and installed Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 10
Computer Sabotage Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 11
Computer Sabotage Denial of service (DoS) attack: Act of sabotage that floods a Web server with so much activity that it is unable to function Distributed DoS attack: Uses multiple computers Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 12
Computer Sabotage Data or program alteration: When a hacker breaches a computer system in order to delete or change data Students changing grades Employees performing vengeful acts, such as deleting or changing corporate data Web site defacement (cybervandalism): Changing content of a Web site Often used to make political statements Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 13
Protecting Against Unauthorized Access, Use, and Computer Sabotage Access control systems: Used to control access to: Facilities Computer networks Databases Web site accounts Can be individual or part of a complete network access control (NAC) system Can be: Identification systems: Verify that the person trying to access the facility or system is an authorized user Authentication systems: Determine if the person is who he or she claims to be Can use more than one type (two-factor systems) Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 14
Access Control Systems Possessed knowledge access systems: Use information that only an individual should know Usernames PINs Passwords Should be strong passwords and changed frequently Tokens can generate passwords Cognitive authentification systems: Use information the individual knows (past teachers, birthplace, first home, etc.) Disadvantage: Can be used by an unauthorized individual with the proper knowledge Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 15
Passwords Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 16
Possessed Knowledge Systems Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 17
Access Control Systems Possessed object access systems: Use physical objects that an individual has in his or her possession Smart cards RFID-encoded badges Magnetic cards Encoded badges USB security keys or e-tokens Disadvantage: can be lost or used by an unauthorized individual When used with passwords or biometrics = two-factor authentication Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 18
Access Control Systems Biometric access systems: Use a unique physical characteristic of an individual in order to grant access Fingerprint Hand geometry Face Iris Can also use personal traits, such as voice or signature Increasingly being built into hardware Advantage: Can only be used by the authorized individual and cannot be lost or forgotten Disadvantage: Cannot be reset ; expensive Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 19
Biometric Systems Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 20
Access Control Systems Controlling access to wireless networks In general, Wi-Fi is less secure than wired networks Security is usually off by default; wireless networks should be secured Wireless network owners should: Enable Wi-Fi encryption (WPA is more secure than WEP) Not broadcast the network name Change the default network administrator password Can use Media Access Control (MAC) address filtering Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 21
Controlling Access to Wireless Networks Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 22
Protecting Against Unauthorized Access, Use, and Computer Sabotage Firewall: Security system that provides a protective boundary between a computer or network and the outside world Works by closing down all external communications port addresses Blocks access to the PC from outside hackers Blocks access to the Internet from programs on the user s PC unless authorized by the user Important for home PCs that have a direct Internet connection as well as for businesses Intrusion protection system (IPS) software is related Monitors and analyzes traffic allowed by the firewall to try and detect possible attacks Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 23
Firewalls Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 24
Protecting Against Unauthorized Access, Use, and Computer Sabotage Encryption: Method of scrambling e-mail or files to make them unreadable Private key encryption: Uses a single key Most often used to encrypt files on a PC If used to send files to others, the recipient needs to be told the key Public key encryption: Uses two keys Public key: Can be given to anyone; used to encrypt messages to be sent to that person Private key: Only known by the individual; used to decrypt messages that are encrypted with the individual s public key Key pairs can be obtained through a Certificate Authority Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 25
Encryption Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 26
Protecting Against Unauthorized Access, Use, and Computer Sabotage Secure Web pages: Use encryption (SSL, EV SSL, etc.) to protect information transmitted via their Web pages Look for a locked padlock on the status bar and https:// in the URL Only transmit credit card numbers and other sensitive data via a secure Web server Web-based encrypted e-mail (HushMail) is available Various strengths of encryption available Stronger is more difficult to crack Strong = 128-bit (16-character keys) Military = 2,048-bit (256-character keys) Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 27
Protecting Against Unauthorized Access, Use, and Computer Sabotage Virtual private networks (VPNs): Secure path over the Internet Allows authorized users to securely access a private network via the Internet Much less expensive than a private secure network since uses the Internet Can provide a secure environment over a large geographical area Typically used by businesspeople to remotely access corporate networks via the Internet Personal VPNs can be used by individuals to surf safely at a wireless hotspot Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 28
Protecting Against Unauthorized Access, Use, and Computer Sabotage Antivirus software: Used to detect and eliminate computer viruses and other types of malware Should be set up to run continuously to check incoming e-mail messages, instant messages, and downloaded files Should be set up to scan the entire PC regularly Needs to be updated regularly since new malware is introduced at all times Best to have the program automatically download new virus definitions on a regular basis Some programs also scan for other threats, such as spyware, bots, possible phishing schemes, etc. Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 29
Antivirus Software Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 30
Protecting Against Unauthorized Access, Use, and Computer Sabotage Some ISPs filter include virus checking E-mail authentication systems can protect against viruses sent via e-mail Common sense precautions can help prevent a virus infection Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 31
Protecting Against Unauthorized Access, Use, and Computer Sabotage Individuals should take additional precautions when using public hotspots in addition to using security software, secure Web pages, VPNs, and file encryption Turn off file sharing Disable Wi-Fi and Bluetooth if not needed Use firewall to block incoming connections Turn off automatic and ad hoc connections Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 32
Protecting Against Unauthorized Access, Use, and Computer Sabotage A significant number of security breaches (over 60%) are committed by insiders Taking caution with employees can help avoid security problems Screen potential new hires carefully Watch for disgruntled employees and exemployees Develop policies and controls Use data-leakage prevention and enterprise rightsmanagement software Ask business partners to review their security to avoid attacks coming from someone located at that organization Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 33
Data-Leakage Prevention Software Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 34
Online Theft, Fraud, and Other Dot Cons Dot con: A fraud or scam carried out through the Internet Data theft or information theft can be committed by: Stealing an actual PC A hacker gaining unauthorized access Includes personal data, proprietary corporate information, and money Identity theft Using someone else s identity to purchase goods or services, obtain new credit cards or bank loans, or illegally masquerade as that individual Information obtained via documents, phishing schemes, stolen information, etc. Expensive and time consuming to recover from Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 35
Identity Theft Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 36
Online Theft, Fraud, and Other Dot Cons Online auction fraud: When an item purchased through an online auction is never delivered, or the item is not as specified by the seller Internet offer scams: A wide range of scams offered through Web sites or unsolicited e-mails Loan and pyramid scams Work-at-home cons and bogus prize offers Nigerian letter fraud scheme Spoofing: Making it appear that an e-mail or a Web site originates from somewhere other than where it really does Web site spoofing E-mail spoofing Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 37
Online Theft, Fraud, and Other Dot Cons Phishing: Use of spoofed e-mail messages to gain credit card numbers and other personal data After victim clicks a link in the message and supplies sensitive data, they transmit that data to the thief E-mails and Web sites often look legitimate Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 38
Online Theft, Fraud, and Other Dot Cons Spear phishing: Targeted to specific individuals Often include personalized information to seem more legitimate May impersonate someone in your organization, such as from human resources or the IT dept. Pharming: The use of spoofed domain names to obtain personal information DNS servers are hacked to route requests for legitimate Web pages to spoofed Web pages (DNS poisoning) Often take place via company DNS servers Drive-by pharming: Hacker changes the DNS server used by a victim s router or access point to use a DNS server set up by the pharmer Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 39
Online Theft, Fraud, and Other Dot Cons Spyware: Program installed without the user s knowledge that secretly collects information and sends it to an outside party via the Internet Can be installed: With another program (particular freeware programs) By clicking a link in a phishing e-mail message By visiting a Web site Security risk if it transmits personal data that can be used in identity theft or other illegal activities Can also slow down a PC or make it malfunction Stealthware: Aggressive spyware programs Often continually deliver ads, change browser settings, etc. Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 40
Protecting Against Online Theft, Fraud, and Other Dot Cons Protecting against identity theft Do not give out personal information (Social Security number, mother s maiden name, etc.) unless absolutely necessary Never give out sensitive information over the phone or by e-mail Shred documents containing sensitive data, credit card offers, etc. Don t place sensitive outgoing mail in your mailbox Watch your bills and credit report to detect identity theft early Can get a free credit report from 3 major consumer credit bureaus each year Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 41
Protecting Against Identity Theft Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 42
Protecting Against Online Theft, Fraud, and Other Dot Cons Protecting against other dot cons: Use common sense Check online auction seller s feedback before bidding Pay for online purchases via a credit card so transactions can be disputed if needed Never respond to e-mail request for updated credit card information Never click a link in an unsolicited e-mail Keep your browser and operating system up to date Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 43
Protecting Against Online Theft, Fraud, and Other Dot Cons Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 44
Protecting Against Online Theft, Fraud, and Other Dot Cons Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 45
Protecting Against Online Theft, Fraud, and Other Dot Cons Protecting against spyware: Check Web sites that list known spyware programs before downloading a program Run antispyware programs regularly Be cautious about downloads Keep operating system and browser up to date Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 46
Protecting Against Online Theft, Fraud, and Other Dot Cons Digital signature: Unique digital code that can be attached to an e-mail message or document Can be used to verify the identity of the sender Can be used to guarantee the message or file has not been changed Uses public key encryption Document is signed with the sender s private key The key and the document create a unique digital signature Signature is verified using the sender s public key Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 47
Protecting Against Online Theft, Fraud, and Other Dot Cons Digital certificate: Group of electronic data that can be used to verify the identity of a person or organization Obtained from a Certificate Authority Typically contains identity information about the person or organization, an expiration date, and a pair of keys to be used with encryption and digital signatures Are also used with secure Web sites to guarantee that the site is secure and actually belongs to the stated individual or organization Can be SSL or EV SSL Banks and other financial institutions may soon issue digital certificates to customers to protect against dot cons Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 48
Protecting Against Online Theft, Fraud, and Other Dot Cons Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 49
Personal Safety Issues Cyberbullying: Bullying someone via the Internet or e- mail Increasingly happening to children and teenagers Cyberstalking: Repeated threats or harassing behavior via e-mail or another Internet communication method including: Sending harassing e-mail messages to the victim Sending unwanted files to the victim Posting inappropriate messages about the victim Signing the victim up for offensive material Publicizing the victim s contact information Sometimes escalates to personal violence Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 50
Personal Safety Issues Online pornography Concern for parents and schools Difficult to stop due to constitutional rights Online pornography involving minors is illegal Link between online pornography and child molestation Internet can make it easier to arrange dangerous meetings between predators and children Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 51
Protecting Against Cyberstalking and Other Personal Safety Concerns Safety tips for adults Be cautious in chat rooms, discussion groups Use gender-neutral, nonprovocative names Do not reveal personal information Do not respond to insults or harassing comments Request to have personal information removed from online directories Safety tips for children Parents should monitor Internet activities Have children use a PC in a family room They should be told which activities are allowed Instruct them to tell a parent of a request for personal information or a personal meeting Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 52
Network and Internet Security Legislation It is difficult for the legal system to keep pace with the rate at which technology changes There are domestic and international jurisdictional issues Computer crime legislation continues to be proposed and computer crimes are being prosecuted Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 53
Network and Internet Security Legislation Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 54
Summary Why Be Concerned about Network and Internet Security? Unauthorized Access, Unauthorized Use, and Computer Sabotage Protecting Against Unauthorized Access, Unauthorized Use, and Computer Sabotage Online Theft, Fraud, and Other Dot Cons Protecting Against Online Theft, Fraud, and Other Dot Cons Personal Safety Issues Protecting Against Cyberstalking and Other Personal Safety Concerns Network and Internet Security Legislation Chapter 4 Understanding Computers in a Changing Society, 3 rd Edition 55