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






2. Process of transforming plaintext into unreadable format






3. 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.






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






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






6. Protects against removing or installing a bogus hard drive using sealing (measuring system variables - BIOS - boot sector - firmware)






7. 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






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






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






10. Method of encryption and decryption






11. Security enhancement for MIME - provides signed (SHA-1) and encrypted (RSA and Diffe-Helman) email messasges






12. RSA - Diffie and Hellman - Elliptic Curve (EC) - DSS (Digital Signature Standard) - El Gamal - Merkel-Hellman






13. Runs on top of TLS on port 443 - protected against MITM attacks and creates secure connections






14. Block and stream






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






16. Tunneling protocol that merges PPTP with L2F - using port 1701 - is used over UDP - can be combined with IPSec for 5 layered encapsulation






17. A special mathematical function that peforms one way encryption - popular algorithms are SHA and MD - used to verify message/file integrity and passwords






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






19. PKI standard






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






21. Based on use of one private/secret key - does NOT provide authentication or nonrepudiation - uses MAC






22. PGP and SSH






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






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






25. An algorithm developed to secure wireless - improperly implemented RC4 - only had a 40 bit key






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






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






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






29. Altering the form of a message to disguise its meaning






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






31. Uses symmetric key for integrity and confidentiality (bulk transaction) and asymmetric key for authentication - nonrepudiation - and key exchange






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






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






34. Unencrypted text - also called cleartext






35. Tunneling protocol originally used on UNIX - uses port 22 - typically used for remote administration - replaces telnet and FTP






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






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






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






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






40. Sender/receiver share the same key - fast - provides confidentiality - key management issue






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






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






43. Art of hiding communications - i.e. hide information in graphic files - sound files - or slack space.






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






45. Process of transforming ciphertext into plaintext (decipherment)






46. PPTP - L2TP - IPSec - and SSH






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






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






49. 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






50. HMAC stands for...