Introduction

• What are the three security services?
• What is Masquerading or Spoofing?
• Based on what you learn so far, what technique(s) can be used to defeat spoofing?
• What types of threats are Torjan horses, according to Shirey's classification?
• What security service defend against DDoS?

Basic Cryptography

• Break the following monoalphabetic cipher. The plaintext, consisting of letters only. Show all your cryptoanalsys steps.
• How many the operation modes exist in AES? Understanding those operating modes.
  

OpenSSL

• Given the certificate of the sender and an ciphertext encrypted with the sender private key, what are the OpenSSL commands that can be used to decipher the text and authenticate the sender?
• What are common information that is included in the certificate request?
• To have one's certificate signed a CA, does one send in one's public key besides the certificate request? How about the private key?
• What is the OpenSSL command that a CA uses to sign the certificate? Does the signing requires CA's private key? Does the signed certificate includes CA's public key?
• How can someone, who receives a certificate signed by Verisign from a web server, verify that indeed the certificate is actually signed by Verisign?
• What common file format is used to save keys and certificates generated by OpenSSL?

Design Principles

• What is the Complete Mediation Principle? Point out a case where the current Unix system does not follow this principle?
• Which design principle in Chapter 13 is closely related to the Kerckhof's Principle in page 7 of the Basic Crypto viewgraphs?

Bell LaPadula Model, Data General B2 and Trusted Solaris 8 implementation.

• What is Multi-Level Directory?
• Can a user with [TS A B] see the files in a directory with [S A]? If not, what he should do?
• Exercises related to dominate relationship.
• What is WURD?
• Which property of Bell LaPadula Model specifies restriction to write down?
• Which property of Bell LaPadula Model specifies restriction to read up?
• What are the strong/weak tranquility?
• Does the get-read and give-read rules change the system state? What part of the system state gets changed in each case?