Cryptography Flashcards
Which of the following types of algorithms encrypts specified sizes of groups of text at a time?
Asymmetric
Streaming
Block
Block
Block algorithms encrypt entire groups of bits of text, usually of specific sizes
You must implement a cryptography system in your organization. You need to be able to send large amounts of data, quickly, over the network. The system will be used by a very small group of users only, and key exchange is not a problem. Which of the following should you consider?
Asymmetric cryptography
Symmetric cryptography
Hybrid cryptography
Symmetric cryptography
In this scenario, symmetric key cryptography would probably be the best choice, since the user group is very small and key exchange is not a problem. You also have the requirements of speed and efficiency, as well as the ability to send large amounts of data. All are advantages of using symmetric key cryptography
Which of the following asymmetric algorithms uses a maximum key size of 4096 bits?
AES
Diffie-Hellman
RSA
RSA
RSA uses key sizes between 1024 and 4096 bits
Which of the following asymmetric algorithms is widely used on mobile devices because of its low computational power requirements?
ECC
ElGamal
Diffie-Hellman
ECC
Elliptic curve cryptography (ECC) is an asymmetric algorithm widely found in use on mobile devices because it requires low amounts of computational power
Which type of algorithm is typically used to encrypt data-at-rest?
Symmetric
Asymmetric
Streaming
Symmetric
Symmetric algorithms are typically used to encrypt data that resides in storage
Which of the following places secrecy of the key versus secrecy of the algorithm as the most important factor in developing secure and reliable cryptosystems?
Data Encryption Standard (DES)
Advanced Encryption Standard (AES)
Kerckhoffs’ principle
Kerckhoffs’ principle
Kerckhoffs’ principle states that reliable cryptosystems should depend upon the secrecy of the key, rather than the secrecy of the algorithm
Which of the following algorithms produces a 40-character message digest?
MD5
SHA-1
RIPEMD-128
SHA-1
SHA-1 is a 160-bit hashing algorithm that produces a 40-character hexadecimal message digest, or hash
If an individual encrypts a message with his own private key, what does this assure?
Confidentiality
Message authenticity
Integrity
Message authenticity
If an individual encrypts a message with his private key, this ensures message authenticity, since he is the only person who could have encrypted it
Which of the following entities can help distribute the workload of the CA by performing identification and authentication of individual certificate requestors?
Root CA server
Authentication authority
Registration authority
Registration authority
The registration authority (RA) can help distribute the workload of the CA by performing identification and authentication of individual certificate requestors
Which of the following serves as the master certificate server in an organization?
Intermediate CA server
Root CA server
Subordinate CA server
Root CA server
A root CA server is the master certificate server in an organization
