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






2. Password storage hash for Windows XP - separates password into two 7 character parts and converts to upper case






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






4. Block and stream






5. 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






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






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






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






9. AES Encryption standard used to protect sensitive but ________ - default key 128






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






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






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






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






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






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






16. Encrypted text - also called cryptogram






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






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






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






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






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






22. PKI standard






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






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






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






26. An algorithm developed to secure wireless that uses AES (CCMP + AES)






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






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






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






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






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






32. PPTP - L2TP - IPSec - and SSH






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






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






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






36. Process of transforming plaintext into unreadable format






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






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






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






40. Method of encryption and decryption






41. HMAC stands for...






42. PGP and SSH






43. Unencrypted text - also called cleartext






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






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






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






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






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






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






50. 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