CHAPTER 7

Question 1

Key management is critical for proper protection. The following are responsibilities that fall under the key management umbrella:

Answer 1

• The key length should be long enough to provide the necessary level of protection.
• Keys should be stored and transmitted by secure means.
• Keys should be extremely random, and the algorithm should use the full spectrum of the keyspace.
• The key’s lifetime should correspond with the sensitivity of the data it is protecting. (Less secure data may allow for a longer key lifetime, whereas more sensitive data might require a shorter key lifetime.)
• The more the key is used, the shorter its lifetime should be.
• Keys should be backed up or escrowed in case of emergencies.
• Keys should be properly destroyed when their lifetime comes to an end.

Question 2

This chapter presents the following:

Answer 2

• History of cryptography
• Cryptography components and their relationships
• Steganography
• Algorithm types
• Public key infrastructure (PKI)
• e-mail standards
• Quantum cryptography
• Secure protocols
• Internet security
• Attack types

Question 3

In reality, encryption can happen at different layers of an operating system and network stack. The following are just a few examples:

Answer 3

• End-to-end encryption happens within the applications.
• SSL encryption takes place at the transport layer.
• PPTP encryption takes place at the data link layer.
• Link encryption takes place at the data link and physical layers.