Computer Concepts Computer Concepts --Illustrated Illustrated Introductory, Seventh EditionIntroductory, Seventh EditionUNIT F:Data SecurityKnowing What Can Go WrongKnowing What Can Go WrongWhat can go wrong?¾ Power outages¾ Hardware failures¾ Software failures¾ Human error¾ Computer viruses¾ Less common threats include natural disasters, acts of war, security breaches, malicious hackers, and theftComputer Concepts – Illustrated Introductory, Seventh EditionProtecting Computer SystemsProtecting Computer SystemsPower protection¾ UPS (uninterruptible power supply)Surge strip (surge protector, surge suppressor)¾ Designed to protect electrical devices from power surges and voltage spikesComputer Concepts – Illustrated Introductory, Seventh EditionUnderstanding AuthenticationUnderstanding AuthenticationTwo-factor authentication¾ Verifies identity using two independent elements of confirmationUser ID¾ Also known as username, login, screen name, online nickname, handlePassword¾ Verifies user ID and guarantees that you are the person you claim to beComputer Concepts – Illustrated Introductory, Seventh EditionUnderstanding AuthenticationUnderstanding AuthenticationRestricting access to computer¾ Keep it in locked room when not in use¾ Password protection and authenticationUser rights¾ Rules that limit directories and files each user can accessComputer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareMalware¾ Malicious code - one of biggest threats to your computer securityComputer virus, worms, trojan horses, zombie, spyware…Computer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareViruses can¾ Corrupt files¾ Destroy data¾ Display irritating message¾ Disrupt operations¾ Deliver payload or trigger event• Time bombs, logic bombsBoot sector virus¾ Infects system files computer uses every time it turns onComputer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareComputer worm¾ Self-copying program designed to carry out unauthorized activity on victim’s computer¾ Able to spread themselves from one computer to another¾ Enter through security holes in browsers and OSs¾ Usually sent via emails or by victims clicking infected pop-up ads or links contained in emails¾ Can even infect mobile phones¾ Mass-mailing worm spreads by sending itself to every address on infected computerComputer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareComputer Concepts – Illustrated Introductory, Seventh EditionSimulated Worm AttackExploring Security ThreatsExploring Security Threatsand Malwareand MalwareTrojan horse¾ Computer program seems to perform one function while actually doing something else¾ Not designed to spread to other computers¾ Notorious for stealing passwords using keyloggerRemote Access Trojan (RAT)¾ Backdoor capabilities that allow remote hackers to• Transmit files to victim’s computer• Search for data• Run programs• Use victim’s computer as relay station for breaking into other computersComputer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareBot¾ Software that can automate task or autonomously execute task when commanded to do so• Called intelligent agent¾ Because intelligent agent behaves like robot, often called botZombie¾ Computer under control of botBotmaster¾ Person who controls many bot-infested computers and can link them together into network called botnetComputer Concepts – Illustrated Introductory, Seventh EditionExploring Security ThreatsExploring Security Threatsand Malwareand MalwareSpyware¾ Program that secretly gathers personal information without victim’s knowledge¾ Usually for advertising and commercial purposes¾ Can piggyback on seemingly legitimate freeware or shareware downloads¾ Can also allow spyware into computer by:• Clicking infected pop-up ads• Surfing through seemingly valid and secure but compromised Web sitesComputer Concepts – Illustrated Introductory, Seventh EditionAvoiding Security ThreatsAvoiding Security Threatsand Malwareand MalwareMay not even be aware that computer is infectedSymptoms of infected computer include¾ Irritating messages or sounds¾ Frequent pop-up ads (often pornographic in nature)¾ Sudden appearance of new Internet toolbar¾ Addition to favorites listComputer Concepts – Illustrated Introductory, Seventh EditionAvoiding Security ThreatsAvoiding Security Threatsand Malwareand MalwareMore symptoms of infected computer¾ Prolonged system start-up¾ Slower than usual response to clicking or typing¾ Browser or application crashes¾ Missing files¾ Disabled security¾ Network activity when not actively browsing or sending email¾ Frequent rebootingComputer Concepts – Illustrated Introductory, Seventh EditionAvoiding Security ThreatsAvoiding Security Threatsand Malwareand MalwareKeeping your computer safe¾ Install and activate security software¾ Keep software patches and operating system service packs up to date¾ Do not open suspicious email attachments¾ Obtain software only from reliable sources¾ Use security software to scan for malware¾ Do not click pop-up ads¾ Avoid unsavory Web sites¾ Disable option Hide extensions for known file types in WindowsComputer Concepts – Illustrated Introductory, Seventh EditionExercisesWrite your answers and send them to [email protected]: exercises Concept Unit F-1Explain the following terms in computer security:¾ Virus¾ Worm¾ Trojan