1. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Digital Certification Kittiphan Techakittiroj engktc@au.ac.th

2. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Digital Signature & Certification Identification –something the person knows, e.g. password –something the person has, e.g. ID card –something the person is, e.g. fingerprint

3. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Digital Signature & Certification To verify who is who. Put identification in the electronics form make it difficult to create one without permission http://www.verisign.com/

4. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Digital Signature public key algorithm use private key to encrypt your information: usually short information make public key (for decryption) available for everyone –can be sent with the message people who get message know it from “you” Digital Signature & Certification

5. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Benefit Major –Confidentiality: encrypted e-mail –Data Integrity: software signature Minor –Authentication: guarantee the encryption source, not the person who encrypt –Non-repudiation: can be done after authentication Digital Signature & Certification: Digital Signature

6. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Digital Certification third party to certify your information using the public key method only authority can encrypt information decryption key are available: can also sent with encrypted data authority need to be trusted by others Digital Signature & Certification

7. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Example Digital Signature & Certification: Digital Certification http://www.data.com/roundups/images/certificate_figure1.html

8. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Category Certificate Authority certificate Individual Certificate: for person, company Server Certificate: for server Software Publisher Certificate: to verify the integrity of the software Digital Signature & Certification: Digital Certification

9. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Standard: X.509 Digital Signature & Certification: Digital Certification http://www.data.com/roundups/images/certificate_figure1.html owner’s public key owner’s name attributes associated with owner: e.g. e-mail name of encryption algorithm issuer or signer expiration date

10. Kittiphan Techakittiroj (24/08/58 22:49 น. 24/08/58 22:49 น. 24/08/58 22:49 น.) Reference Books Developing Secure Commerce Applications by Online O’Reilly Web Development Courses (http://208.233.153.3/oreilly/security/westnet: 1999) Client/Server Survival Guide by Robert Orfali, Dan Harkey, Jeri Edwards (John Wiley & Sons: 1999)