信息安全技术复习题目最终版Word文件下载.docx

1、（2）自动取款机使用了DES数据加密，相当于一个加密系统，有时候密码未泄露，但犯罪份子知道了身份信息和银行卡号后能够盗取卡里的钱。 这个案例中的安全问题有：个人信息泄露，财产的损失。ATM using DES data encryption, is an cryptography system, sometimes the password does not leak, but criminals steal the money after know the identity information and bank card number .The security problem in t

2、his case are: personal information leakage, the loss of the property.3. Among the fundamental challenges in information security are confidentiality, integrity, and availability, or CIA. A. Define each of these terms: confidentiality, integrity, availability.B. Give a concrete example where confiden

3、tiality is more important than integrity.C. Give a concrete example where integrity is more important than confidentiality.D. Give a concrete example where availability is the overriding concern.Answer：A.Confidentiality is of the information with a certain degree of secrecy only for authorized perso

4、n to read and change it; Integrity is to prevent or at least to detect unauthorized changes to information; Availability is that the legally ownes and users for information, they have access to the information at any time if they need.B.The document about State secrets.C.Test scores.D.E-commerce sit

5、e. To avoid service interruption, lead to users and their own interests is damaged, its availability is the most important。翻译：信息安全领域的基本挑战包括机密性、完整性和可用性，或者简称CIA。A.请给出机密性、完整性、可用性的术语定义。答：机密性具有一定保密程度的信息只能让有授权的人读取和更改；完整性是防止或至少检测出对信息进行未授权的修改；可用性是对于信息的合法拥有和使用者，在他们需要这些信息的任何时候，都应该保障他们能够及时得到所需要的信息。4. Suppose t

6、hat we have a computer that can test 240 keys each second.*What is the expected time （in years） to find a key by exhaustive search if the keyspace is of size288?*What is the expected time （in years） to find a key by exhaustive search if the keyspace is of size2112?*What is the expected time （in year

7、s） to find a key by exhaustive search if the keyspace is of size2256?Anwser:（1）288/240=248 second 248/（60*60*24*365）=8.923*106 （2）2112/240=272 second 272/（60*60*24*365）=1.497*106（3）2256/240=2216 second 2216/（60*60*24*365）=3.339*10575. Give four strong passwords derived from the passphrase “Gentlemen

8、 do not read other gentlemens mail.” And describe how to derive your answer from the passphrase.6. Give four strong passwords derived from the passphrase “Are you who you say you are?”. And describe how to derive your answer from the passphrase.根据Are you who you say you are随便构造4个强密码并解释构造方法。例如1ReNwNs

9、1yNA 此题要求独创性强密码长度至少有 8 个字符，不包含全部或部分用户帐户名，不包含完整的单词,至少包含以下四类字符中的三类:大写字母、小写字母、数字，以及键盘上的符号（如 !、#）。7. For each of the following passwords, give two passphrase that the password could have been derived from.A: PokeGCTall B: 4s&7vrsaC: gimmeliborD D: IcntgetNOsat例如：A.PokeGCTallPerson or kids end Good Cat T

10、all Play on kid Great Cool Top are like like8. Consider the ciphertext FALSZ ZTYSY JZYJK YWJRZ TYJZT YYNAR YJKYS WARZT YEGYY J, which was generated using an affine cipher with parameter a=7 and b=22. Decipher the message please.加密过程为：E（m）=（am+b）mod26解密过程为：c（m）=a-1（c-b）mod26=7-1（c-22）mod26=15（c-22）mo

11、d26 所以仿射码解密相对应的字母为123456789101112明文ABCDEFGHIJKLM密文WRYTOV13141516171819202122232425NPQSUXZ密文：FALSZ ZTYSY JZYJK YWJRZ TYJZT YYNAR YJKYS WARZT YEGYYJ明文：first the sentence and then the evidence said the queen.9. Consider the ciphertext QJKES REOGH GXXRE OXEO, which was generated using an affine cipher.

12、Determine the constants a&b and decipher the message. Hint: Plaintext “t” encrypts to ciphertext“H” and plaintext “o” encrypts to ciphertext“E”.加密过程：a,b are constants（常数），p is plaintext（明文），C is ciphertext（密文）So a=11 ,b= 6解密过程：c（m）=a-1（c-b）mod26=11-1（c-6）mod26序号abcdefghijklmnopqrstuvwxyzCiphertext（密

13、文）:QJKES REOGH GXXRE OXEOPlaintext（明文）:If you bow at all bow low.10. Please give three examples of authentication based on “something you know”, “something you have” and “something you are”;a.Passwordauthentication（something you know）b.Security token and a smart card（something you have）c. Biometric

14、authentication is the use of fingerprints or face scanning and iris（虹膜） or voicerecognition，iris type or fingerprints scanned（something you are）a.密码验证b.安全令牌和智能卡c.生物特征识别11. Two-factor authentication requires that two of the three authentication methods （something you know, something you have, somethi

15、ng you are） be used. Give two examples from everyday life where two-factor authentication is used. Which two of the three are used?1.Use the bank card to withdraw money in ATM. Bank card is something you have and password is something you know. 2.Use the ID card and the admission notice to verify id

16、entity,whenentering the university. ID card and the admission notice are something you have, oneself is something you are .双重认证要求的两三个身份验证方法（你知道的东西,你拥有的东西,你是什么）被使用。给两个例子从日常生活使用双重认证。使用了其中的哪两个因素？First example,ATM card, of which the user must hold a card and PIN number.”something you have” and “somethin

17、g you know” are used on ATM cards.Other examples of two-factor authentication include credit card with handwritten signature. “something you have” and “something you are” are used on this method.12. RFID tags are extremely small devices capable of broadcasting a number over the air that can be read

18、by a nearby sensor. RFID tags are used for tracking inventory, and they have many other potential uses. For example, RFID tags are used in passports and it has been suggested that they should be put into paper money to prevent counterfeiting. In the future, a person might be surrounded by a cloud of

19、 RFID number that would provide a great deal of information about the person.*Discuss some privacy concerns related to the widespread use of RFID tags.*Discuss security issues, other than privacy, that might arise due to the widespread use of RFID tags.（1）Illegal to read the information（非法读取信息）、Posi

20、tion location tracking（位置定位跟踪）（2）Interfere with the correct receiving information（干扰正确信息接收）、counterfeiting（伪造假币）1.非法读取信息；RFID tags offer way to illegal read of the information about customers.位置定位跟踪.RFID tags could be used to track peoples movements, determine their identities or make inferences abo

21、ut their habits（用来追踪人们的动作,确定他们的身份或推断他们的习惯）2.拒绝服务：人为的信号干扰使合法的阅读器不能正常读取标签数据；Denial of service :Artificial interference make the legal reader cant read the label data properly.重放：根据窃听到的阅读器和标签之间的数据通信，重复之前的通信行为从而获得信息数据。The replay:According to hacking into the data communication between the reader and the

22、 tag, repeat previous data communication behavior in order to gain information.13. Decrypt the following message that was encrypted using a simple substitution cipher:WB WI KJB MK RMIT BMIQ BJ RASHMWK RMVP YJERYRKB MKD WBI IWOKWXWVMKVR MKD IJYR YNIB URYMWKNKRASHMWKRD BJ OWER M VJYSHRBR RASHMKMBWJK J

23、KR CJNHD PMER BJLR FNMHWXWRD MKD WKISWURD BJ INVPMK RABRKB BPMB PR VJNHD URMVP BPR IBMBR JXRKHWOPBRKRD YWKD VMSMLHR JX URVJOKWGWKOIJNKDHRII IJNKD MKD IPMSRHRII IPMSR W DJ KJB DRRY YRIRHX BPR XWKMH MNBPJL WBT LNB YT RASRL WRKVRCWBP QMBM PMI HRXB KJ DJNLB BPMB BPR XJHHJCWKO WIBPR SUJSRU MSSHWVMBWJK MKD WKBRUSURBMBWJK WJXXRU YT BPRJUWRI WK BPR PJSR BPMB BPR RIIRKVR JX JQWKMCMK QMUMBR CWHH URYMWK WKBMVB14. This problem deals with digital signat