BFOR 203 Final - Hashing-Symmetric-Asymmetric

Which one of the following algorithm is not used in asymmetric-key cryptography? A. rsa algorithm B. diffie-hellman algorithm C. Advanced Encryption Standard D. none of the mentioned

Advanced Encryption Standard

Symmetric encryption provides (choose all that apply) A. Confidentiality B. Integrity C. Availability D. Authenticity E. Non-Repudiation

Confidentiality/ Integrity/Availability

asymmetric encryption provides (choose all that apply) A. Confidentiality B. Integrity C. Availability D. Authenticity E. Non-Repudiation

Confidentiality/Integrity/Availability/Authenticity/Non-Repudiation

A common hash algorithm no longer considered secure is? A. AES B. DES C. MD5 D. RSA E. RC4

MD5

Common Hash algorithms (choose all that apply) A. MD5 B. RSA C. AES D. 3DES E. SHA1

MD5/SHA1

Which is the largest disadvantage of the symmetric Encryption? A. More complex and therefore more time-consuming calculations. B. Problem of the secure transmission of the Secret Key. C. Less secure encryption function. D. Rarely used.

Problem of the secure transmission of the Secret Key.

the following is a stream cipher A. AES B. DES C. RC4 D. RSA E. none of the above

RC4

Hash algorithm based on MD hash A. RSA B. ECC C. Keccak D. SHA1 E. SHA3

SHA1

In cryptography, what is cipher? A. algorithm for performing encryption and decryption B. encrypted message C. both (A) and (B) D. none of the mentioned

algorithm for performing encryption and decryption

Diffie Hellman (choose best answer) A. is a key exchange algorithmm B. is used to begin symmetric encryption C. is often used during asymmetric encryption to pass a key D. all of the above

all of the above

What is data encryption standard? A. block cipher B. stream cipher C. bit cipher D. none of the above

block cipher

A hash will... A. be a variable length file B. encrypt the data in a file C. be reversible D. always be the same if the data is the same.

called public key encryption/ used for digital signatures

Asymmetric encryption is (choose all that apply) A. Stream cipher only B. called public key encryption C. Uses a single key D. used for digital signatures E. all of the above

called public key encryption/used for digital signatures

Hashing should make: A. data encrypted B. conversion back to the original data impossible C. asymmetric encryption possible D. symmetric encryption possible

conversion back to the original data impossible

A cryptographic hash function takes an arbitrary block of data and returns A. fixed size bit string B. variable size bit string C. reversible string D. none of the above

fixed size bit string

DES (choose all that apply) A. is a block Cipher B. has been cracked C. is less secure than AES D. is a stream cipher E. uses 256-bit encryption

is a block Cipher/ has been cracked/ is less secure than AES

RSA (choose all that apply) A. is slower than DES B. is faster than symmetric encryption C. is an asymmetric algorithm D. uses prime numbers E. has been deprecated

is slower than DES/ is an asymmetric algorithm/ uses prime numbers

In asymmetric key cryptography, the private key is kept by A. sender B. receiver C. sender and receiver D. all the connected devices to E. the network

receiver

Block ciphers are (choose all that apply) A. slower than stream ciphers when text is short B. more prone to attack C. More secure D. divided into equal length plaintext for encryption E. all of the above

slower than stream ciphers when text is short/More secure/divided into equal length plaintext for encryption

Why are hash values of files often stored online with the file? A. so you can verify the file is the original B. so you can decrypt the file C. so you can identify the creator of the file D. to confirm the size of the file

so you can verify the file is the original

Is Bob sends a message to Alice and the message content hash is 543 but when Alice gets the email the hash of the message contents is 544... what does this mean? A. the message has been decrypted B. the message has been encrypted C. the message has been changed D. the message is the original and the ttl has increased by 1

the message has been changed

Cryptanalysis is used... A. to find some insecurity in a cryptographic stream B. to increase speed of the algorithm C. to encrypt the data D. to create cryptographic alorithms

to find some insecurity in a cryptographic stream

which of the following is used to secure an HTTP connection? A. stream control transmission protocol B. transport layer security C. secure standards layer D. hypertext transport header encryption E. markup language encryption

transport layer security

In cryptography, the order of the letters in a message is rearranged by A. transpositional ciphers B. substitution ciphers C. both (A) and (B) D. none of the mentioned

transpositional ciphers

Symmetric key algorithms A. use a private/public key B. use a single key C. use a hash algorithm D. are all block Ciphers E. are all stream Ciphers

use a single key

If I XOR 1 and 1... what is the result? A. 2 B. 1 C. 0 D. none of the above

0

If I XOR 0 and 1... what is the result? A. 2 B. 1 C. 0 D. none of the above

1

If I XOR 11010 and 01011... what is the result? A. 10001 B. 10100 C. 01110 D. 01010 E. none of the above

10001

Which of the following algorithms are symmetric encryption? A. 3DES (TripleDES) B. RSA C. RC5 D. IDEA

3DES (TripleDES)/RC5/ IDEA

Two different sets of data creating an identical hash is considered what in the cryptography field? A. A mistake B. Impossible C. A collision D. A cipher anomaly

A collision

Which is the principle of the encryption using a key? A. The key indicates which function is used for encryption. Thereby it is more difficult to decrypt a intercepted message as the function is unknown. B. The key contains the secret function for encryption including parameters. Only a password can activate the key. C. All algorithms are public, only the key is secret. It contains the parameters used for the encryption resp. decryption. D. The key prevents the user of having to reinstall the software at each change in technology or in the algorithms for encryption.

All algorithms are public, only the key is secret. It contains the parameters used for the encryption resp. decryption.

Repudiation in cryptography is A. Denying the sending of a message B. Not being able to deny the sending of a message C. Deciphering of a message D. Reputation

Denying the sending of a message

Hash algorithms ensure? A. Confidentiality B. Reference C. Absolution D. Availability E. Integrity

Integrity

If I change the data in a file I have compromised its A. Confidentiality B. Integrity C. Availability D. Authenticity E. Repudiation

Integrity

Which are categories of cryptographic algorithms? A. Symmetric B. RSA C. Data Encryption Standard D. Hashing

Symmetric/Hashing

Cryptography is: A. The process of converting from plaintext to ciphertext B. A scheme C. Techniques used for deciphering a message without any knowledge of the enciphering details D. The areas of cryptology and cryptanalysis E. The area of study of the many schemes used for encryption

The area of study of the many schemes used for encryption

How does IPsec, TLS, SSL combine symmetric and asymmetric encryption? A. First, the message is encrypted with symmetric encryption and afterwards it is encrypted asymmetrically together with the key. B. The secret key is symmetrically transmitted, the message itself asymmetrically. C. First, the message is encrypted with asymmetric encryption and afterwards it is encrypted symmetrically together with the key. D. The secret key is asymmetrically transmitted, the message itself symmetrically.

The secret key is asymmetrically transmitted, the message itself symmetrically.