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UESTIONS
1.1 The OSI Security Architecture is a framework that provides a systematic way of defining
the requirements for security and characterizing the approaches to satisfying those
requirements. The document defines security attacks, mechanisms, and services, and the
relationships among these categories.
1.2 Passive attacks have to do with eavesdropping on, or monitoring, transmissions.
Electronic mail, file transfers, and client/server exchanges are examples of
transmissions that can be monitored. Active attacks include the modification of
transmitted data and attempts to gain unauthorized access to computer systems.
1.3 Passive attacks: release of message contents and traffic analysis. Active attacks:
masquerade, replay, modification of messages, and denial of service.
1.4 Authentication: The assurance that the communicating entity is the one that it claims to be.
Access control: The prevention of unauthorized use of a resource (i.e., this service controls
who can have access to a resource, under what conditions access can occur, and what those
accessing the resource are allowed to do).
Data confidentiality: The protection of data from unauthorized disclosure.
Data integrity: The assurance that data received are exactly as sent by an authorized entity
(i.e., contain no modification, insertion, deletion, or replay).
Chapter 1: Introduction ..................................................................................................5
Chapter 2: Classical Encryption Techniques ...............................................................7
Chapter 3: Block Ciphers and the Date Encryption Standard ................................13
Chapter 4: Finite Fields .................................................................................................21
Chapter 5: Advanced Encryption Standard ..............................................................28
Chapter 6: More on Symmetric Ciphers ....................................................................33
Chapter 7: Confidentiality Using Symmetric Encryption .......................................38
Chapter 8: Introduction to Number Theory ..............................................................42
Chapter 9: Public-Key Cryptography and RSA ........................................................46
Chapter 10: Key Management; Other Public-Key Cryptosystems ...........................55
Chapter 11: Message Authentication and Hash Functions .......................................59
Chapter 12: Hash and MAC Algorithms .....................................................................62
Chapter 13: Digital Signatures and Authentication Protocols ..................................66
Chapter 14: Authentication Applications ....................................................................71
Chapter 15: Electronic Mail Security ............................................................................73
Chapter 16: IP Security ...................................................................................................76
Chapter 17: Web Security ...............................................................................................80
Chapter 18: Intruders ......................................................................................................83
Chapter 19: Malicious Software ....................................................................................87
Chapter 20: Firewalls ......................................................................................................89
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