Test your basic knowledge |

Comptia Security +: Cryptography

Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. PGP and SSH






2. Method of encryption and decryption






3. Technique of encapsulating one packet of data within another type to create a secure link of transportation






4. Developed to strengthen DES - uses 3 keys (key clustering) to encrypt 3 times






5. Enciphers fixed-size blocks of bits using substitution and permutation






6. Cipher block chaining (CBC) - cipher feedback (CFB) - electronic code book (ECB) and output feedback (OFB)






7. DES - 3DES - AES - Twofish - Blowfish - IDEA - Skipjack - RC2 -RC4 - RC5 - RC6






8. Developed to replace DES based on Rijndael variable block cipher - has a fixed block length and key lengths: 128 - 192 - or 256 bits






9. Free email security program that uses several algorithms - symmetric (IDEA) - asymmetric (RSA) and hashes (SHA1) and the web of trust






10. Encryption standard broken in 1998 - has a relatively short key length






11. Common tunneling protocol integrated in Windows - works well with NAT - maybe blocked at firewall






12. Process of transforming plaintext into unreadable format






13. Cryptographic algorithm that operates on plaintext - one bit at a time - and enciphers with a random generated "key stream" using substitution






14. PKI standard






15. Most widely used tunneling protocol - over port 1723 - data carried in an IP tunnel over Generic Routing Encapsulation (GRE)






16. Two different pieces of data have the same hash value






17. A cryptographic communications protocol at the transport layer that provides public key encryption (RSA or Diffie-Helman) - data encryption (IDEA - DES - 3DES) - server authentication - message integrity (MD5 or SHA-1) - and client authentication.






18. Symmetric cryptography - asymmetric cryptography - and hashes provide __________






19. Encrypting all data on a disk using common algorithms (AES) - requires a key (passpharse - USB key) in memory to decrypt disk






20. Selected by NIST for cryptographic hash functions for public use - 160 bit length






21. Digital signature standard that uses 2 algorithms: RSA and DSA (based on El Gamal) - both use the Secure Hash Standard (SHA-1)






22. Pads messages to a length of 512 bits - then compresses to generate a 128 bit hash value






23. Used by WPA - uses RC4 with IV - blocks replay attacks with packet sequence counter - replaced by WPA2






24. Sequence of bits used in encryption and decryption - also known as cryptovariable






25. Impossible to find a message - given only message digest - impossible to find 2 messages that produce the same message digest






26. Block and stream






27. Process of transforming ciphertext into plaintext (decipherment)






28. Based on two keys - public and private - one-way function: a key cannot decrypt what it encrypts - provides confidentiality - authentication - integrity - and nonrepudiation - Discovered by Diffie and Hellman - also known as public key






29. An internet email standard format specifying how multimedia and attachments are handled






30. Symmetric cryptography with MAC - asymmetric cryptography - and hashes provide __________






31. Allow client/server applcation to communicate in a secure manner across a network - TLS stands for






32. A protocol suite for securing network connections using IKE - AH - and ESP






33. For encrypting web communications - uses Cryptographic Messaging Syntax (CMS) to protect individual message and response






34. Has a transport and tunnel mode - tunnel mode is used to create VPN connections






35. Password storage hash for Windows systems after XP - uses MD4 and full unicode character set






36. Discovering the original message using other than normal means (i.e. "breaking" the cryptosystem)






37. Asymmetric cryptography - hashes - and digital signatures provide __________






38. Provides digests in different lengths including 224 - 256 - 384 - and 512






39. Mechanism for message authentication that uses one of two algorithms (SHA-1 or MDF5) in combination with a shared secret key - also known as keyed hashing






40. A secure cryptoprocessor embedded in the motherboard used to authenticate a hardware device - TPM stands for






41. Unencrypted text - also called cleartext






42. The cipher considered unbreakable in practice - uses XOR - also called the Vernam cipher






43. Encrypting a message's hash value with a private key - DOES NOT ensure confidentiality






44. Most efficient algorithm - used for smart cards and cell phones - provides digital signatures - secure key exchange - and encryption






45. Most widely used asymmetric algorithm - used for digital signatures - key exchange - and encryption






46. A cryptographic protocol that provides security for communications over networks such as the Internet - more secure that SSL






47. PPTP - L2TP - IPSec - and SSH






48. A cryptographic checksum used to provide integrity in symmetric key cryptography






49. Provides integrity - authentication - and non-repudiation by encrypting a message digest with a private key






50. Data encryption standard derived from IBM Lucifer algorithm - 56-bit key - 64-bit block - uses the Data Encryption Algorithm (DEA)