首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A variety of simple techniques can prevent computer crime. For example, destroying printed information, protecting computer scre
A variety of simple techniques can prevent computer crime. For example, destroying printed information, protecting computer scre
admin
2010-12-25
40
问题
A variety of simple techniques can prevent computer crime. For example, destroying printed information, protecting computer screens from observation. Keeping printed information and computers in locked cabinets, and clearing desktops of sensitive documents prevent access to confidential information. But more sophisticated methods are also necessary to prevent computer crimes.
One technique to protect confidentiality is encryption. Information can be scrambled and unscrambled u-sing mathematical equations and a secret code called a key. Two keys ale usually employed, one to encode and the other to decode the information. The key that encodes the data, called the private key, is possessed by only the sender. The key that decodes the data, called the public key, may be possessed by several receivers. The keys are modified periodically, further hampering unauthorized access and making the encrypted information difficult to decode or forge.
Another technique to prevent computer crime is to limit access of computer data files to approved users. Access control software verifies computer users and limits their privileges to view and alter files. Records can be made of the files accessed, thereby making users accountable for their actions. Military organizations give access rights to classified, confidential, secret, or top-secret information according to the corresponding security clearance level of the user. Passwords are confidential sequences of characters that give approved users access to computers. To be effective, passwords must be difficult to guess. Effective passwords contain a mixture of characters and symbols that are not real words.
Tokens are tamper-resistant plastic cards with microprocessor chips that contain a stored password that automatically and frequently changes. When a computer is accessed using a token, the computer reads the token’s password, as well as another password entered by the user, and matches these two to an identical list In the future, passwords and tokens may be reinforced by biometrics, identification methods that use u-nique personal characteristics, such as fingerprints, retinal patterns, skin oils, deoxyribonucleic acid (DNA), voice variations, and keyboard-typingrhythms.
Computer networks, multiple computers linked together, are particularly vulnerable to computer crimes. Information on networks can be protected by a firewall, a computer placed between the networked computers and the network. The firewall prevents unauthorized users from gaining access to the computers on a network, and it ensures that information received from an outside source does not contain computer viruses, self-replicating computer programs that interfere with a computer’s functions.
According to paragraph 2 , the keys are changed frequently in order to______.
选项
A、encode more data
B、decode more data
C、give people more private keys
D、make information difficult to decode
答案
D
解析
文章指出,密钥定期改良,进一步阻止了未经允许的访问,并使加密信息难于解密。第二段Thekeys are modified periodically further hampering unauthorized access and makingthe encrypted infor-mation difficult to decode or forge.
转载请注明原文地址:https://jikaoti.com/ti/IZXYFFFM
0
考博英语
相关试题推荐
Jennifer’scell-phonenumberis
Youwillheartwotelephoneconversations.Writedownonewordornumberinthespacesontheformsbelow.Message1Questions
Whyaretelephonenumberschanging?
Howmuchshouldthemanpay?
Howmuchshouldthemanpay?
Lookatthepassagebelow.Someinformationismissing.Youwillhearawomantalkingaboutpersonalexperience.Foreachquesti
•Readthefollowingpassageaboutsuccessfulbusinessexecutives.•Arethesentences16-22"Right"or"Wrong"?Ifthereisn’t
Animportantpointinthedevelopmentofagovernmentalagencyisthecodificationofitscontrollingpractices.Thestudyofla
【S1】HomescouldstartbeenconnectedtotheInternetthroughelectricaloutlets.【S2】Inthisway,consumersandbusinessmayfi
Wemustsafeguardagainstcoercedconfessions.
随机试题
Thefourth-gradersatChicago’sMcCormickElementarySchooldon’tknowChineseissupposedtobehardtolearn.Formost,whosp
国内肝细胞癌的分型包括
男性患者,因外伤致股骨内外踝骨折,关节面不平,相差0.8cm,虽经治疗,骨折移位未见改变,最可能出现的晚期并发症是
2012年10月,中国制造业采购经理指数(PMI)为50.2%,比上月上升0.4个百分点,重新回到临界点之上。分企业规模看,大型企业PMI为50.9%,比上月上升0.7个百分点,连续2个月位于临界点以上;中型企业PMI为49.3%,比上月下降0.
国家采用法律形式规定的,适龄儿童、少年都必须接受的,国家、社会、学校、家庭都必须予以保证的,带有强制性的国民教育称为()。
Scientistscanpredictregions______newspeciesaremostlikelytobefound.
FiveCommonMistakesinConversationandTheirSolutionsI.NotlisteningA.Problem:mostpeopledon’tlisten—waiteagerlyf
StayingSmart:AdviceonNavigatingYourCareerMillionsofcareerchangesoccureachyear.Somearenatural,butmanymore
Inoursociety,therearemanyethicaldilemmasthatwearefacedwiththatarevirtuallyimpossibletosolve.Oneofthemostd
A、Theyareahappycouple.B、Theyaxetiresome.C、Theyarebad-tempered.D、Theyareverygoodpeople.D根据选项,推测对话的内容与评价相关,对话中出现了“
最新回复
(
0
)