Kĩ thuật lập trình - Chương 9: Personal technology

1Personal Technology9.1 Truth Issues: Manipulating Digital Data9.2 Security Issues: Threats9.3 Security: Safeguarding Computers & Communications9.4 Quality-of-Life Issues9.5 Economic & Political IssuesChapter9McGraw-Hill/Irwin© 2007 The McGraw-Hill Companies, Inc. All rights reserved.Truth Issues: Manipulating Digital DataDigital Images and Sounds can be manipulatedPro: Creates new forms of artMorphing software makes one image morph into another Movies such as “Crouching Tiger, Hidden Dragon” and “Harry Potter” contain many scenes that could never actually happenAdobe Photoshop allows changes, enhancements to photosDigital technology allows musicians to sing every track of a song and accompany themselvesCon: Has made photographs & recordings untrustworthyFamous Yalta summit photo edited: Stallone added in! 3Truth Issues: Manipulating Digital DataPhotographs may not be authenticPhotographs may be deliberately misleading1994 Time magazine photo of O.J. Simpson was digitally darkened to make him appear sinisterCould this have biased potential jury members? Fashion model photos are routinely elongated to make models appear more slenderHow many girls become anorexic to try to match those models’ impossible perfection? 4Truth Issues: Manipulating Digital DataTechniques to combat digital deceptionProf. William H. Mitchell of M.I.T. wrote the first systematic, critical analysis of the digital revolution Corbis adds a digital watermark to its photosHany Farid of Dartmouth College devised algorithms to detect changes to uncompressed digital photosProf. Jessica Fridrich of S.U.N.Y. at Binghamton is researching digital cameras that hide a picture of the photographer’s iris inside each digital photo 5Truth Issues: Manipulating Digital DataLimitations of Public databases You can’t get the whole storyStart with a public database, THEN do more researchThe data is not necessarily accurateCross-check against multiple sourcesEach database service has boundariesKnow what those boundaries areDifferent keywords bring different resultsHistory is limitedThese databases often begin with data from 1980 or later6Security Issues: ThreatsErrors and accidentsNatural hazardsComputer crimeComputer criminalsIs my computer safe?I’m concerned about it. What do I need to do to use it safely for work, home, and school?7Security Issues: ThreatsErrors & AccidentsHuman errorsPeople choose the wrong computerToo simple or too complexHuman emotions affect performancePeople get frustratedHuman perceptions are slower than the equipmentWatch out when you click the OK button! You may have just deleted something important!8Security Issues: ThreatsErrors & AccidentsProcedural errorsWhen people fail to follow safe procedures, errors can occurSoftware errorsProgrammers make coding errorsFamous example: Utility billing software:Customer pays early – software credits accountCustomer pays late – software credits account, adds late fee in for next billProgrammer forgot to consider customers who pay exactly on time – their payments were never credited at all!9Security Issues: ThreatsErrors & AccidentsElectromechanical problemsMechanical systems wear outPower failures shut down computers unless you have battery backupUsing cellphones and Blackberries while driving can cause people to crashDirty data problemsIncomplete, updated, or inaccurate dataCheck your records – medical, school, and credit to make sure they are accurateNatural hazards can lead to disasters10Security Issues: ThreatsComputer CrimesTwo types of computer crimeIt can be an illegal act perpetrated against computers or telecommunicationsIt can be the use of computers or telecommunications to accomplish an illegal act11Security Issues: ThreatsComputer CrimesTheft of hardwareTheft of softwareTheft of online music and videosTheft of time and servicesTheft of informationInternet-related fraudTaking over your PCCrimes of maliceComputer criminals12Security Issues: ThreatsComputer CrimesTheft of hardware can range fromShoplifting an item from a computer storeStealing an entire PC or laptopTheft of softwarePirated software is software obtained illegallyThis includes “softlifting” - buying one copy of the software and using it on multiple computersSoftware makers have prosecuted both companies and individuals including students for software piracy13Security Issues: ThreatsComputer CrimesTheft of online music and moviesEntertainment industry takes this seriously and prosecutes offendersStealing musicIllegal file swapping servicesDamages can be up to $150,000 per songStealing moviesThe film industry has taken aggressive aim at pirated movies11-nation crackdown announced in 200514Security Issues: ThreatsComputer CrimesTheft of time and servicesTheft of computer time at workSurfing or playing games when you should be workingSome employees violate policy by conducting personal business online such as online auctions from workMost employers have policies against viewing X-rated web sites at workTheft of phone servicesPhone phreaks use company phone systems to make “free” unauthorized long distance callsWhy break the law, when you can get free long distance over the internet using skype www.skype.com 15Security Issues: ThreatsComputer CrimesTheft of InformationA common crime todayCan include theft of personal information, medical information, or credit card and financial informationLegislation to make it a crime to steal someone’s identity was the 1998 Identity Theft and Assumption Deterrence ActThe U.S. Department of Justice discusses their approach to this crime at If you are a victim of identity theft, you may file a report online at the Federal Trade Commission’s website at https://rn.ftc.gov/pls/dod/widtpubl$.startup?Z_ORG_CODE=PU03 16Security Issues: ThreatsComputer CrimesInternet-related FraudBecause it lends itself to anonymity, internet-related fraud is becoming more commonWell-known examples include:Nigerian letter scamLetter says you can get a lot of money out of Nigeria if you pay a “money transfer fee” firstEvil twin attacksA cracker sets up an attack computer as a duplicate public access point in a public locationPhishingSending emails that appear to come from a trusted source that links you to a website where you type in personal information that is intercepted by the phisher17Security Issues: ThreatsComputer CrimesInternet-related Fraud (continued)PharmingMalicious software is implanted in your computer that directs you to an imposter web pageTrojan horsesA program such as a “free” online game or screensaver that loads hidden programs that take over your computer or cause mischief without your knowledgeFor example, Windows users who install the phony MSN Messenger Version 8 "beta" are actually installing an IM worm that spreads to their IM contacts, and connects their computer to a remote control "bot" network run by malicious hackers18Security Issues: ThreatsComputer CrimesCrimes of Malice: Crashing entire computer systemsSometimes criminals are more interested in vandalizing systems than they are in gaining control of themIn 2003, an entrepreneur with a grudge because he lost a sale retaliated by shutting down the WeaKnees websiteCrackers regularly attempt to crash Microsoft’s websiteSecurity specialists monitor for possible cyber-attacks on electrical and nuclear power plants, dams, and air traffic control systemsCrackers have attacked the internet too and brought down large sections of it19Security Issues: ThreatsComputer CrimesComputer criminals may includeIndividuals or small groups whoUse fraudulent email and websitesSteal peoples’ identities for monetary gainsShow off their power for bragging rightsEmployees whoHave a grudge against their current or former employersHave a grudge against another employeeSell their company’s secrets for personal profitOutside partners and company suppliers20Security Issues: ThreatsComputer CrimesComputer criminals may also includeCorporate spiesEnemy foreign intelligence services Organized crimeTerrorists Computer criminals do not include your employer, who is legally allowed to monitor the computers at workCheck your company’s computer usage policyMake sure you follow the rulesKnow that any data you store in the computer at work – including emails – is company property21Security: SafeguardingComputers & CommunicationsSecurity is A system of safeguards for protecting information technology against disasters, system failures, and unauthorized access that can result in damage or lossComputer Security’s Five ComponentsDeterrence of computer crimeIdentification and accessEncryptionProtection of software and dataDisaster recovery plans22Security: SafeguardingComputers & CommunicationsDeterrents to computer crimeEnforcing lawsCERT: The Computer Emergency Response TeamProvides round-the-clock information on international computer security threatsThe CERT website is www.cert.org For example, on December 15, 2005 announced a partnership between the US and ictQatar, the Qatar Supreme Council for Information and Communications Technology, to conduct and coordinate cybersecurity activitiesOn December 13, 2005 CERT issued alert SA05-347A documenting Windows Explorer vulnerabilities23Security: SafeguardingComputers & CommunicationsMore deterrents to computer crimesTools to fight fraudulent and unauthorized online usesRule-based detection softwarePredictive-statistical-model softwareEmployee internet management softwareInternet filtering softwareElectronic surveillanceVerify legitimate right of accessUse cards, keys, signatures, and badgesUse PINs and passwordsUse physical traits and personal identification24Security: SafeguardingComputers & CommunicationsEncryptionThe process of altering readable data into unreadable form to prevent unauthorized accessAdvantage: encrypting data that is available over the internet keeps thieves and crackers from reading itOn Dec. 7, 2005, Guidance Software, a maker of Computer Forensics software, informed their customers that criminals had stolen their credit cards because Guidance had FAILED to encrypt a database that was accessible over the internetDisadvantage: encrypting data may prevent law-enforcement officials from reading the data criminals are sending to each other Discussion Question: Does information privacy outweigh law enforcement’s needs to track down and prosecute criminals? Should we all encrypt our information to prevent crackers and criminals from stealing it?25Security: SafeguardingComputers & Communications4 ways to protect software & dataEducate employees in backing up data, virus protection, and not sharing passwordsControl of access to restrict usageAudit controls to document who used what programs and computers and whenPeople controls include screening applicants, background checks, monitoring internet, email, and computer usage26Security: SafeguardingComputers & CommunicationsDisaster-recovery plansA method of restoring information-processing operations that have been halted by destruction or accidentReinforced by 2001 World Trade Center attackReinforced by company data losses incurred during 2005 Hurricane KatrinaPlans range in price and complexity fromBacking up data from disk to tape, CD, or zip disk, with a UPSAutomatically storing data redundantly in two places, with a generatorHaving an off-site computerized data storage center with independent power supplyHaving a complete “hot” redundant data center that can instantly be used if there is a disasterMore $$$27Quality-of-Life IssuesInformation Technology misuse can result in Environmental problemsManufacturing computers and circuits can cause pollutionComputer component manufacturing employees may be exposed to toxic substancesUsed computers/monitors contain chromium, cadmium, lead, mercury, PVC, and brominated flame retardants – all toxic substances that must be disposed of properlyExacerbation of Mental-health problems Proliferation of pornography Workplace problems28Quality-of-Life IssuesInformation Technology misuse can result in Environmental problemsExacerbation of mental-health problems Isolation; computer gamers may substitute online games for interpersonal interactionOnline gambling can be addictiveMany users find PCs stressfulInternet usage by children can expose them to online predatorsProliferation of pornography Workplace problems29Quality-of-Life IssuesInformation Technology misuse can result in Environmental problemsExacerbation of Mental-health problems Proliferation of pornographyOnline pornographers use pop-up ads and internet search engines to troll for new customers This means that children may be exposed to porn when involved in innocent online searchesParents may use online blocking software like Cybersitter, Cyber Patrol, or Net Nanny to prevent thisWorkplace problems30Quality-of-Life IssuesParental Responses to protecting children from online pornOnline blocking softwareDVD filtersVideogame rating systemsThe V-chipSupport legislation to require pornographers to use certain web addresses, such as .xxx domainMonitor internet useBe candid to your children about the threatsSave evidence and block messages to prevent cyberbullying31Quality-of-Life IssuesInformation technology misuse can result in Environmental problemsExacerbation of mental-health problems Proliferation of pornographyWorkplace problemsMisuse of technologyFussing with computers can waste timeInformation overload32Economic & Political IssuesTechnology may affect the gap between the rich and the poorMost jobs require employees who are tech-savvyPeople who are not tech-savvy won’t qualify for those jobsTechnology is being used to replace employees in traditional jobs, traditionally filled by untrained workersInternet is not controlledThis means that information moves freely on the internetNondemocratic governments can’t control internet political activismInternet is only loosely policed, so criminals take advantage33