Test your basic knowledge |

CCIE Sec Encryption Ipsec

Subjects : cisco, it-skills, ccie
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. You check it by hashing data and appending the hash value to the data as you send it across the network to a peer.






2. Uses IKE for key exchange.






3. Main disadvantage of asymmetric algorithms is that they are slow.






4. Can be implemented efficiently on a wide range of processors and in hardware.






5. Used for integrity checks on peer and data sent by peer and for authentication checks.






6. Hybrid protocol that defines the mechanism to derive authenticated keying material and negotiation of security associations (SA).






7. DoS attacks are more probable with this mode.






8. 'Message digest algorithms have a drawback whereby a hacker (man in the middle) can intercept a message containing the packet and hash values - then re-create and transmit a modified packet with the same calculated hash to the target destination.'






9. 'Three keys encrypt the data - which results in a 168-bit encryption key. The sending device encrypts the data with the first 56-bit key.'






10. The protocol of choice for key management and establishing security associations between peers on the Internet.






11. 'Encryption - where Peer X uses Peer Y






12. It also provides protection for ISAKMP peer identities with encryption.






13. 'DSA is roughly the same speed as RSA when creating signatures - but 10 to 40 times slower when verifying signatures. Because verification happens more frequently than creation - this issue is worth noting when deploying DSA in any environment.'






14. IPsec implements using a shim header between L2 and L3






15. Message of arbitrary length is taken as input and produces as output a 128-bit fingerprint or message digest of the input.






16. The receiving device then encrypts the data with the second key.






17. 'in most cases - this mode is preferred with certificates.'






18. 'group 2 identifies a 1024-bit key - group 2 is more secure - but slower to execute.'






19. Negotiation of a shared secret key for encryption of the IKE session using the D-H algorithm


20. More CPU intensive






21. Negotiation of the ISAKMP policy by offering and acceptance of protection suites






22. RFC 2631 on the workings of the key generation/exchange process.






23. 'group 5 identifies a 1536-bit key - provides for highest security but is the slowest of all groups.'






24. Uses the D-H algorithm to come to agreement over a public network.






25. Provides authentication and encryption of the payload.






26. 'often called public-key algorithms - do not rely on a randomly generated shared encryption key; instead - they create two static keys. These static keys are completely different - but mathematically bound to each other; what one key encrypts - the o






27. Is a two-phase protocol: The first phase establishes a secure authenticated channel and the second phase is where SAs are negotiated on behalf of the IPsec services.






28. The DES algorithm that performs 3 times sequentially.






29. ' is defined in RFC 3174. has as output a 160-bit value -'






30. 'including Internet Security Association and Key Management Protocol (ISAKMP) - Secure Key Exchange Mechanism for the Internet (SKEME) - and Oakley.'






31. Provide authentication in Internet Key Exchange (IKE) Phase 2.






32. You use this encryption method by keeping one key private and giving the other key to anyone in the public Internet. It does not matter who has your public key; it is useless without the private key.






33. 'provides everything required to securely connect over a public media - such as the Internet.'






34. Act of encapsulating a packet within another packet.






35. ID exchange and authentication of D-H key by using the reply to the received nonce or string of bits


36. IPSEC tunnels data through IP using one of two protocols?






37. 'key lengths are 128 - 192 - or 256 bits to encrypt blocks of equal length.'






38. 'The messages are authenticated - and the mechanisms that provide such integrity checks based on a secret key are usually called'






39. 'requires that the sender and receiver have key pairs. By combining the sender






40. 'Created by NIST in 1994 - is the algorithm used for digital signatures but not for encryption.'






41. Used in IPsec for two discreet purposes:






42. Benefits are that the preshared authentication can be based on ID versus IP address and the speed of the process.






43. The sending device encrypts for a final time with another 56-bit key.






44. Uses protocol number 50.






45. 'group 1 identifies a 768-bit key - group 1 is faster to execute - but it is less secure -'






46. 'A 56-bit encryption algorithm - meaning the number of possible keys






47. Data integrity is the process of making sure data is not tampered with while it






48. 'The sending device decrypts the data with the second key - which is also 56 bits in length.'






49. Turns clear-text data into cipher text with an encryption algorithm. The receiving station decrypts the data from cipher text into clear text. The encryption key is a shared secret key that encrypts and decrypts messages.






50. Does not provide payload encryption.