Review Questions

• 7.1 For a user workstation in a typical business environment, list potential locations for confidentiality attacks.

• Eavesdropping on the LAN itself
• A remote access point such as dial-in
• Wiring closet
• Routers that connect to the internet
• On any line that your traffic traverses e.g.
  • the local telephone company
  • Point-to-point terrestrial links (microwave, wireless etc.)
  • Satellite communication

  7.2 What is the difference between link and end-to-end encryption?

Link encryption happens between links in this way it is much harder to determine the source and destination because routing information is encrypted between each link. However the message is still vulnerable at the switches themselves, so you need end-to-end encryption to guarentee that switches not under your controll are not releasing the message.

For more see Table 7.1 Characteristics of Link and End-to-End Encryption

• 7.3 What types of information might be derived from a traffic analysis attack?

• Who is communicating
• The type of communication

• 7.4 What is traffic padding and what is its purpose?

  7.5 List ways in which secret keys can be distributed to two communicating parties.

  7.6 What is the difference between a session key and a master key?

  7.7 What is a nonce?

  7.8 What is a key distribution center?

  7.9 What is the difference between statistical randomness and unpredictability?