1. Public Key Infrastructure Ben Sangster February 23, 2006

2. Outline ● What is Public Key Infrastructure (PKI)? ● Functions and Components of PKI ● How does PKI work? ● Present day use of PKI ● Future of PKI ● Questions

3. What is Public Key Infrastructure? (also known as PKI) ● Technology that enables users to securely and privately exchange data over an unsecured medium without the loss of integrity or confidentiality ● Also manages how user and network resources are identified and given access to online information and services

4. Functions and Components of PKI ● Certification authority (CA) ● Registration authority (RA) ● PKI clients ● Digital certificates ● Certificate Distribution System or repository ● Keys (Public and Private)

5. Functions of PKI (cont.) ● Certificate Requests ● Certificate Revocation ● Client to Client Interaction ● Timestamping ● Non-repudiation ● Cross-certification

6. How does PKI work? ● Entities – Host A, B – RA, CA ● Objects – Public Keys for all entities – Private Keys for all entities – Digital Certificate – Hash Function – Message

7. Examples (Private Key, Certificate, Certificate Request) ● Sample Private Key (2048 bits, TXT format) Sample Private Key (2048 bits, TXT format) ● Sample CA Certificate (TXT format) Sample CA Certificate (TXT format) ● Sample Certificate Request (TXT format) Sample Certificate Request (TXT format)

8. PKI Entities

9. Example of Certificate Request and Distro Architecture

10. Present Day Example of PKI in Use ● U. S. Department of Defense ● Canadian Government ● Corporate World ● Academia

11. DOD PKI

12. Future of PKI ● Eventually, same distribution of PKI enabling hardware and software as we have seen in the growth of computers in homes and businesses ● The emergence and growth of e-commerce gives validity to PKI and its future (but PKI does not give e-commerce validity)

13. Questions