1. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 1 Introduction Known Information Software Complexity Encryption Schemes Secure Web Documents Digital Signatures Firewalls

2. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 2 Introduction Volunteered Information Information Collection Known Information

3. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 3 Telephone listings Public events Company profile Known Information Introduction

4. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 4 Filling out a form on Web site Known Information Volunteered Information Internet simplifies information collection Search engines Information Collection

5. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 5 Contributing Factors Browsers, Networks, Operating Systems, and Servers Software Complexity

6. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 6 Program size Software interface Market forces Team development Software Complexity Contributing Factors Patches Browsers, Networks, Operating Systems, and Servers

7. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 7 Basic Concepts Prime Numbers Private Key Cryptography Public Key Cryptography Hashing Algorithms Encryption Schemes

8. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 8 Method of encoding information Plaintext Ciphertext Cipher Encryption key Decrypt (decipher) Encryption Schemes Basic Concepts

9. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 9 Whole-number factors are 1 and itself Composite numbers “Almost prime” Key Encryption Schemes Prime Numbers

10. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 10 Sender and receiver share same private key Key used to encrypt plaintext and decrypt Ciphertext Encryption Schemes Private Key Cryptography Authentication Every sender has private key Every person has a public key Public Key Cryptography

11. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 11 Verify the message received is same as sent message Computes value based on plaintext message Encryption Schemes Hashing Algorithms

12. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 12 Whole skeleton key or locked padlock Secure server https Sniffing Secure Web Documents

13. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 13 Introduction Digital Signature Example Pretty Good Privacy Digital Signatures

14. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 14 Mechanism used to officially sign electronic document Verify sender and content of message Digital Signatures Introduction

15. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 15 Sender computes hash of plaintext Sender encrypts hash with public key cryptography Sender encrypts plaintext with private key cryptography Sender sends private-key-encrypted ciphertext Sender sends public-key-encrypted hash Receiver reverses the steps Digital Signatures Digital Signature Example

16. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 16 An email security package 1995 Phil Zimmermann Authentication Compression Digital signature Privacy capabilities Used by Computer Emergency Response Team (CERT) Digital Signatures Pretty Good Privacy

17. Privacy and Security Topics From Greenlaw/Hepp, In-line/On-line: Fundamentals of the Internet and the World Wide Web 17 Security mechanism Protect LANs from Internet Two types of firewall systems: Network layer Proxy servers Firewalls