108 + Interview Questions in Message Authentication Codes in Cryptograph & Network Security Page 1 InterviewSolution

1.	X.509 certificate recommends which cryptographic algorithm?(a) RSA(b) DES(c) AES(d) RabinThe question was asked in an interview.My query is from Public Keys and X.509 Certificates-III topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT choice is (a) RSA To explain: RSA is the recommended cryptographic ALGORITHM for X.509 CERTIFICATES.

Discussion

2.	Given a message and its n-bit hash result, the expected workload of finding a message that hashes to the same value is of the order _______________(a) 2^(n/2)(b) 2^(n-1)(c) 2^(n)(d) 2^(2n)I got this question during an internship interview.The doubt is from Whirlpool Algorithm topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» CORRECT OPTION is (C) 2^(N) The explanation: When the message and hash value are provided, the workload turns out to be 2^n.

Discussion

3.	When the Round Constant is given by S[8(r-1)+j]. What are the limits of ‘i’ and ‘j’?(a) i = 1 ; 0
Answer» Right answer is (B) i = 0 ; 0 <= j <= 7 To explain I would SAY: All rows except the first one are 0 i.e. RC=0 for ‘i’ not equal to 0.

Discussion

4.	MACs are also called(a) testword(b) checkword(c) testbits(d) none of the mentionedThis question was addressed to me in exam.My question is taken from Message Authentication Codes (MACs) in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right CHOICE is (d) none of the mentioned Explanation: ANOTHER TERM for MACs are tags(or check SUM).

Discussion

5.	How many functions are involved in the PKIX architectural model?(a) 3(b) 5(c) 6(d) 7The question was asked in an online interview.I want to ask this question from Public Keys and X.509 Certificates-III topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct CHOICE is (d) 7 Easy explanation: The 7 functions are: REGISTRATION, Initialization, Certification, KEY pair recovery, Key pair update, Revocation request and CROSS certification.

Discussion

6.	Which systems use a timestamp?i) Public-Key Certificatesii) Public announcementsiii) Publicly available directoriesiv) Public-Key authority(a) i) and ii)(b) iii) and iv)(c) i) and iv)(d) iv) onlyI got this question in an interview for job.The question is from Public Keys and X.509 Certificates-I topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right ANSWER is (c) i) and IV) Explanation: Public ANNOUNCEMENTS and Public CERTIFICATES involve the use of timestamps.

Discussion

7.	Which of the following public key distribution systems is most secure?(a) Public-Key Certificates(b) Public announcements(c) Publicly available directories(d) Public-Key authorityThe question was asked in unit test.This interesting question is from Public Keys and X.509 Certificates-I in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT choice is (a) PUBLIC-KEY Certificates The explanation: Public certificates are the most SECURE key distribution/management systems right now.

Discussion

8.	USENET is related to which of the following Public Key distribution schemes?(a) Public-Key Certificates(b) Public announcements(c) Publicly available directories(d) Public-Key authorityI got this question in an interview for internship.I would like to ask this question from Public Keys and X.509 Certificates-I topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct choice is (b) Public announcements For explanation: MANY PGP USERS APPEND their public KEY to messages that they send to public forums, such as USENET and Internet mailing lists.

Discussion

9.	Which session key is used for electronic funds transfer and point of sale applications?(a) Data-encrypting key(b) File-encrypting key(c) PIN-encrypting key(d) None of the mentionedI have been asked this question in an interview for internship.This intriguing question originated from Symmetric Key Distribution in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT option is (c) PIN-encrypting key For explanation: PIN-encrypting key is the SESSION key which is used for ELECTRONIC funds TRANSFER and POINT of sale applications.

Discussion

10.	Which algorithm has the most execution latency?(a) SHA-1(b) SHA-2(c) MD-5(d) WhirlpoolI got this question at a job interview.This is a very interesting question from Whirlpool Algorithm in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct option is (b) SHA-2 The EXPLANATION: Whirlpool has the LOWEST latency. Latency is defined by the number of iteration rounds. SHA-2 has 80 rounds, whereas Whirlpool has 10.

Discussion

11.	Which round provides linear diffusion in the Whirlpool Algorithm?(a) Add Key(b) Substitute Bytes(c) Mix Rows(d) Shift RowsThe question was posed to me in unit test.This key question is from Whirlpool Algorithm in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct OPTION is (C) Mix Rows To elaborate: MR function is the linear DIFFUSION LAYER of the Whirlpool block CIPHER.

Discussion

12.	Which of the following terms is not an input to the CCM encryption?(a) Nonce.(b) Associated data.(c) Plaintext message.(d) Tag.I had been asked this question in final exam.This is a very interesting question from CCM, GCM and Key Wrapping topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct OPTION is (d) Tag. For EXPLANATION I WOULD SAY: A tag is not involved with CCM.

Discussion

13.	Each round uses a different key in the algorithm.(a) True(b) FalseI had been asked this question by my school principal while I was bunking the class.My query is from Whirlpool Algorithm topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct choice is (a) True To explain: Whirlpool PRODUCES keys for each round USING the same ALGORITHM itself. Keys are UPDATED per round.

Discussion

14.	The expected workload of generating a collision is of the order of ____________ executions of Whirlpool.(a) 2^(n/2)(b) 2^(n-1)(c) 2^(n)(d) 2^(2n)I got this question during an interview.The query is from Whirlpool Algorithm in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct ANSWER is (a) 2^(n/2) The explanation: The EXPECTED WORKLOAD of generating a COLLISION is 2^(n/2).

Discussion

15.	CMP stands for(a) cipher message protocol(b) cipher management protocol(c) certificate message protocol(d) none of the mentionedI had been asked this question by my school teacher while I was bunking the class.My enquiry is from Public Keys and X.509 Certificates-III in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT choice is (d) none of the mentioned The EXPLANATION is: CMP stands for certificate management PROTOCOL.

Discussion

16.	A total of seven messages are required in the Public-Key distribution scenario. However, the initial five messages need to be used only infrequently because both A and B can save the other’s public key for future – a technique known as ____(a) time stamping(b) polling(c) caching(d) squeezingI got this question during an internship interview.My doubt stems from Public Keys and X.509 Certificates-III topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct choice is (c) CACHING Easiest explanation: This technique is KNOWN as caching.

Discussion

17.	Suppose that A has obtained a certificate from certification authority X1 and B has obtained certificate authority from CA X2. A can use a chain of certificates to obtain B’s public key. In notation of X.509, this chain is represented in the correct order as –(a) X2 X1 X1 B(b) X1 X1 X2 A(c) X1 X2 X2 B(d) X1 X2 X2 AThe question was asked in a job interview.My question is taken from Public Keys and X.509 Certificates-II topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right option is (C) X1 X2 X2 B For explanation: The CORRECT REPRESENTATION would be X1 X2 X2 B.

Discussion

18.	Which of the following is required to find the session key?i) Control Vectorii) Master Keyiii) Encrypted session Key(a)i)(b) i) and ii)(c) i) and iii)(d) i) ii) and iii)This question was addressed to me in exam.Origin of the question is Symmetric Key Distribution in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right answer is (d) i) ii) and iii) To elaborate: We REQUIRE all THREE to find the SESSION KEY.

Discussion

19.	Which of these is not a type of session key?(a) PIN-encrypting key(b) File-encrypting key(c) Session encrypting key(d) Data encrypting keyThis question was addressed to me in my homework.The doubt is from Symmetric Key Distribution topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right choice is (C) Session encrypting key Best explanation: DATA, PIN and File are the different session keys.

Discussion

20.	Session keys are transmitted after being encrypted by(a) make-shift keys(b) temporary keys(c) master keys(d) section keysI have been asked this question during an interview for a job.Query is from Symmetric Key Distribution in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct choice is (c) master keys For EXPLANATION: Each NODE has a master key which it USES to receive the SESSION key.

Discussion

21.	Communication between end systems is encrypted using a key, often known as(a) temporary key(b) section key(c) line key(d) session keyI have been asked this question during an online exam.My enquiry is from Symmetric Key Distribution in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right OPTION is (d) session KEY The explanation is: The key is REFERRED to as session key.

Discussion

22.	How many add round key functions are present in the Whirlpool algorithm?(a) 16(b) 18(c) 11(d) 10This question was posed to me in exam.This interesting question is from Whirlpool Algorithm topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct answer is (c) 11 Easiest explanation: There are 11 ROUND key addition FUNCTIONS in the Whirlpool algorithm. ONE key addition per round. One key addition before the 1ST round.

Discussion

23.	The message is padded to(a) 1024 bits(b) 512 bits(c) Odd multiple of 256 bits(d) Odd multiple of 512 bitsI have been asked this question in an international level competition.My doubt is from Whirlpool Algorithm in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT answer is (c) ODD multiple of 256 BITS Easy explanation: The MESSAGE in Whirlpool is padded to an odd multiple of 512 bits.

Discussion

24.	How many XOR gate operations are involved in the S-box permutation?(a) 12(b) 8(c) 16(d) 4I had been asked this question in homework.Origin of the question is Whirlpool Algorithm topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right option is (a) 12 The EXPLANATION is: 12 XORs are INVOLVED in the S-box PERMUTATION in Whirlpool.

Discussion

25.	The 7th row in the 8 × 8 matrix undergoes a ___________ shift.(a) 6 bit(b) 6 byte(c) 7 bit(d) 7 byteI got this question in class test.My enquiry is from Whirlpool Algorithm topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right option is (B) 6 BYTE To explain: The NTH row in the 8 × 8 MATRIX undergoes an (n-1) byte shift.

Discussion

26.	The hash matrix is of the size(a) 16 × 8(b) 16 × 4(c) 8 × 8(d) 4 × 16The question was asked by my school teacher while I was bunking the class.This intriguing question originated from Whirlpool Algorithm topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct ANSWER is (C) 8 × 8 To ELABORATE: The hash matrix has a 8 × 8 matrix.

Discussion

27.	The cipher block is one block longer than the plaintext to accommodate the IV.(a) True(b) FalseThe question was posed to me in an interview for internship.I want to ask this question from CCM, GCM and Key Wrapping in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct option is (a) True Explanation: The CIPHER BLOCKS has N+1 cipher blocks, for n plaintext blocks.

Discussion

28.	Certificate extensions fall into 3 categories. Which one of the following is not a Certificate extensions category?(a) Subject and Issuer attributes(b) Key and Policy information(c) Certification path constraints(d) All of the above are Certificate extensions categoriesThis question was posed to me by my college director while I was bunking the class.My query is from Public Keys and X.509 Certificates-III topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct option is (d) All of the above are Certificate extensions CATEGORIES To explain: SUBJECT and Issuer attributes, Key and Policy INFORMATION and Certification path CONSTRAINTS are the three categories of Certificate extensions.

Discussion

29.	The issuer unique identifier of the X.509 certificates was added in which version?(a) 1(b) 2(c) 3(d) 4The question was asked in an online quiz.I would like to ask this question from Public Keys and X.509 Certificates-III in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right answer is (b) 2 For explanation I WOULD say: The ISSUER UNIQUE identifier was added in the 2nd version.

Discussion

30.	The criticality indicator indicates whether an extension can be safely ignored.(a) True(b) FalseThis question was addressed to me in an international level competition.My enquiry is from Public Keys and X.509 Certificates-II topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT OPTION is (a) TRUE Explanation: The STATEMENT is true.

Discussion

31.	If end to end connection is done at a network or IP level, and if there are N hosts, then what is the number of keys required?(a) N(N-1)/2(b) N(c) N(N+1)/2(d) N/2I got this question in my homework.This is a very interesting question from Symmetric Key Distribution topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right option is (a) N(N-1)/2 For explanation I WOULD say: The NUMBER of KEYS required would be N(N-1)/2, SIMILAR to that of a mesh topology network connection (each node is connection line requires a KEY).

Discussion

32.	It is desirable to revoke a certificate before it expires because(a) the user is no longer certified by this CA(b) the CA’s certificate is assumed to be compromised(c) the user’s private key is assumed to be compromised(d) all of the mentionedThis question was addressed to me in an interview for job.Question is from Public Keys and X.509 Certificates-II topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT option is (d) all of the mentioned For EXPLANATION I would say: All of the options are true with REGARD to revocation of a certificate.

Discussion

33.	How many rounds does the Whirlpool algorithm undergo?(a) 12(b) 14(c) 10(d) 16This question was posed to me in class test.My enquiry is from Whirlpool Algorithm in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct option is (C) 10 Best EXPLANATION: There are 10 rounds in the ALGORITHM.

Discussion

34.	What is the correct order of operation within each round of the Whirlpool algorithm?(a) Add round key, Substitute bytes, Mix rows, Shift columns(b) Substitute bytes, Add round key, Shift columns, Mix rows(c) Mix rows, Substitute bytes, Shift columns, Add round key(d) Substitute bytes, Shift columns, Mix rows, Add round keyThe question was asked during an interview.Asked question is from Whirlpool Algorithm in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right option is (d) SUBSTITUTE BYTES, Shift columns, MIX rows, Add round key Easiest EXPLANATION: The CORRECT order is Substitute bytes, Shift columns, Mix rows, Add round key.

Discussion

35.	Before the first round of the Whirlpool algorithm, which is the operation that takes place?(a) Addition of Key(b) Substitution of Bytes(c) Mixing of Rows(d) Shifting of ColumnsI have been asked this question in final exam.My doubt stems from Whirlpool Algorithm topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right choice is (a) ADDITION of Key The best I can explain: Before the first ROUND of the Whirlpool ALGORITHM, addition of key round TAKES place.

Discussion

36.	How many handshake rounds are required in the Public-Key Distribution Scenario?(a) 7(b) 5(c) 3(d) 4This question was addressed to me during an online interview.Query is from Public Keys and X.509 Certificates-III topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» CORRECT option is (a) 7 Explanation: A TOTAL of seven messages are REQUIRED in the Public-Key distribution SCENARIO.

Discussion

37.	Which among the following has not been broken yet( still collision free)?(a) MD-5(b) SHA-1(c) DES(d) SHA-2This question was posed to me in homework.The query is from Whirlpool Algorithm in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct CHOICE is (d) SHA-2 Easy explanation: SHA-2 has not yet been broken, but since SHA-1 has been found to be not COLLISION free (and SHA-2 has the same LOGIC as SHA-1), SHA-3 ALGORITHM was developed and officialised in 2012.

Discussion

38.	CRL stands for(a) Cipher Reusable List(b) Certificate Revocation Language(c) Certificate Revocation List(d) Certificate Resolution LanguageI have been asked this question in an online quiz.The origin of the question is Public Keys and X.509 Certificates-II in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct option is (c) Certificate REVOCATION LIST The explanation is: CRL STANDS for Certificate Revocation List.

Discussion

39.	Which hash algorithm is the most hardware intensive among the following?(a) SHA-1(b) SHA-2(c) MD-5(d) WhirlpoolI have been asked this question in exam.Origin of the question is Whirlpool Algorithm in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» CORRECT CHOICE is (d) Whirlpool Easy EXPLANATION: NONE.

Discussion

40.	Which Authentication Encryption approach is taken by the SSH protocol?(a) Hashing followed by encryption (H→E)(b) Encryption followed by authentication (E→A)(c) Authentication followed by encryption (A→E)(d) Independently encrypt and authenticate (E + A)I had been asked this question in examination.My question is from CCM, GCM and Key Wrapping topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct answer is (d) Independently encrypt and AUTHENTICATE (E + A) To EXPLAIN: Independently encrypt and authenticate (E + A)is the AE approach TAKEN by the SSH protocol.

Discussion

41.	In GCM, we define S as S = GHASH(A\|\|0^v\|\|C\|\|0^u\|\|[len(A)]\|\|[len(C)]). What is u defined as?(a) 64 ceil[len(A)/128] – len(A)(b) 64 ceil[len(C)/128] – len(C)(c) 128 ceil[len(A)/128] – len(A)(d) 128 ceil[len(C)/128] – len(C)This question was posed to me in an internship interview.I'm obligated to ask this question of CCM, GCM and Key Wrapping in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct OPTION is (d) 128 CEIL[LEN(C)/128] – len(C) The best explanation: u = 128 ceil[len(C)/128] – len(C).

Discussion

42.	For an n-bit tag and a k-bit key, the level of effort required for brute force attack on a MAC algorithm is(a) 2^k(b) 2^n(c) min(2^k,2^n)(d) 2^k/2^nThe question was asked in a national level competition.I'd like to ask this question from Message Authentication Codes (MACs) topic in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Correct ANSWER is (C) min(2^k,2^n) For explanation: The LEVEL of effort REQUIRED for brute force attack on a MAC algorithm is min(2^k,2^n).

Discussion

43.	The following figure has authentication tied to the plaintext-(a) True(b) FalseThe question was posed to me during an interview.The query is from Message Authentication Codes (MACs) in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT option is (b) False To EXPLAIN: The FIGURE has authentication TIED to the ciphertext.

Discussion

44.	Which mode of operation is used in the DAA?(a) output feedback mode(b) electronic code block mode(c) cipher block chaining mode(d) cipher feedback modeThis question was posed to me by my college professor while I was bunking the class.The doubt is from HMAC, DAA and CMAC topic in chapter Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The correct answer is (c) CIPHER block CHAINING mode Best explanation: The DAA is an algorithm based on the DES cipher block chaining mode.

Discussion

45.	Which of the following is not an element/field of the X.509 certificates?(a) Issuer Name(b) Serial Modifier(c) Issuer unique Identifier(d) SignatureI have been asked this question in my homework.Question is taken from Public Keys and X.509 Certificates-II topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT OPTION is (B) Serial MODIFIER Explanation: Serial Modifier is not an element/field of the X.509 CERTIFICATES.

Discussion

46.	Which of the following is not true for whirlpool hashing function?(a) It is a two way hashing function(b) It is based on a 512 bit block cipher(c) The block cipher is similar to AES structure(d) It is resistant to differential attacksThe question was asked in an internship interview.My query is from Whirlpool Algorithm in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT ANSWER is (a) It is a two way hashing function The best EXPLANATION: The WHIRLPOOL ALGORITHM is a one way hashing algorithm.

Discussion

47.	Which system uses a trusted third party interface?(a) Public-Key Certificates(b) Public announcements(c) Publicly available directories(d) Public-Key authorityI got this question during an internship interview.The above asked question is from Public Keys and X.509 Certificates-I in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» CORRECT ANSWER is (a) Public-Key Certificates Explanation: Public-Key certificates use a TRUSTED THIRD party interface.

Discussion

48.	CMS stands for(a) cipher message syntax(b) certificate message session(c) cryptographic message syntax(d) none of the mentionedThis question was addressed to me by my school principal while I was bunking the class.The origin of the question is Public Keys and X.509 Certificates-III topic in division Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» RIGHT answer is (C) CRYPTOGRAPHIC message syntax Easy EXPLANATION: CMS stands for cryptographic message syntax.

Discussion

49.	The period of validity consists of the date on which the certificate expires.(a) True(b) FalseThe question was asked during an interview.Enquiry is from Public Keys and X.509 Certificates-III topic in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» The CORRECT choice is (b) False The explanation: The Period of validity CONSISTS of 2 dates: the FIRST and LAST date on which the certificate is VALID.

Discussion

50.	Which of these systems use timestamps as an expiration date?(a) Public-Key Certificates(b) Public announcements(c) Publicly available directories(d) Public-Key authorityThis question was posed to me in a national level competition.I'm obligated to ask this question of Public Keys and X.509 Certificates-I in portion Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security
Answer» Right CHOICE is (a) PUBLIC-KEY Certificates The best explanation: Public key certificates use timestamps as expiration DATES.

Discussion

Explore topic-wise InterviewSolutions in .

When the Round Constant is given by S[8(r-1)+j]. What are the limits of ‘i’ and ‘j’?(a) i = 1 ; 0

How many rounds does the Whirlpool algorithm undergo?(a) 12(b) 14(c) 10(d) 16This question was posed to me in class test.My enquiry is from Whirlpool Algorithm in section Message Authentication Codes, Whirlpool Algorithm and Key Management and Distribution of Cryptograph & Network Security