J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003 1 Chapters 9...

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Chapters 9 & 10, Modern Operating Systems

by A. S. Tanenbaum

Group E

IA705, Spring 2003

IA 705, Prof. Brown, Spring 2003

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Chapter 9, UNIX & LinuxModern Operating Systems

by A. S. Tanenbaum

Group E

IA705, Spring 2003

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Jose Paloschavez

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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The Security EnvironmentThreats

Security goals and threats

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Intruders

Common Categories

1. Casual prying by nontechnical users

2. Snooping by insiders

3. Determined attempt to make money

4. Commercial or military espionage

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Accidental Data Loss

Common Causes

1. Acts of God- fires, floods, wars

2. Hardware or software errors- CPU malfunction, bad disk, MSFT program bugs

3. Human errors- data entry, wrong backup disk

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Basics of CryptographyRelationship between the plaintext and the ciphertext

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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• Monoalphabetic substitution– each letter replaced by different letter

Plaintext: ABCDEFGHI…

Ciphertext: EQHOZGS EGSSTUT

CAPITOL COLLEGE

• Given the encryption key, – easy to find decryption key

• Secret-key crypto called symmetric-key crypto

Secret-Key Cryptography

J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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Public-Key Cryptography

• All users pick a public key/private key pair– publish the public key

– private key not published

• Public key is the encryption key– private key is the decryption key

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J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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J. Paloschavez, M. Troxler, J. Boggs, J. Lagas Chapters 9 & 10 IA705 Spring 2003

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