Growing Up with Alice and Bob: Three Decades with the RSA Cryptosystem

1. Growing Up with Alice and Bob:Three Decades with the RSA Cryptosystem Burt Kaliski, RSA SecurityApril 7, 2006

2. The Vision, c. 1976 Secure communications for everyone, including Alice and Bob: Confidentiality, integrity, non-repudiation

3. The Challenge Alice and Bob don�t have an easy way to set up encryption keys k2 problem for pairwise keys Trusted third parties not always mutual

4. The Technology: Public-Key Cryptography Diffie and Hellman 1976 What if encryption, decryption keys were different? Publish one, keep other secret Alice and Bob can set up keys just by reading a public directory! Diffie-Hellman key agreement achieved most of the goals RSA 1977 has the rest � including digital signatures Contemporaneous work by Merkle, and in classified arena

5. RSA Public-Key Cryptosystem Rivest, Shamir, Adleman 1977 Public key = (n, e) n: modulus, product of two (or more) large random primes p, q e: public exponent, typically 3, or 65537 Private key = (n, d) d: private exponent, such that e*d ? 1 mod (p-1)(q-1) Key observation: Computing private key requires factors of n, and factoring is a hard problem

6. RSA Public-Key Cryptosystem (cont�d) Encryption: c = me mod n Decryption: m = cd mod n Signature: s = md mod n Verification: m =? se mod n

7. The Vision, cont�d Secure communications for everyone, including Alice and Bob, via public-key cryptography:

8. The Vision, cont�d Secure communications for everyone, including Alice and Bob, via public-key cryptography:

9. Other �Characters� in Cryptography Alice and Bob are joined by several other characters in research papers and books (e.g., Schneier�s Applied Cryptography)

10. Lessons Learned along the Road to Commercialization RSA algorithm invented in 1977 Today, the algorithm is in widely implemented How did we get here? 10 lessons learned along the way.

11. #1: Validation Publication, peer review RSA Factoring Challenge RSA Laboratories Cryptographic technologies can take years to validate

12. #2: Partnership IETF Privacy & Security Research Group Lotus Notes� Apple, IBM, Microsoft, Motorola, Novell, Sun, Xerox, �

13. #3: Product Patent license? Hardware circuit? Software application? ? Software development toolkit

14. #4: Marketing RSA Conference Frequently Asked Questions about Today�s Cryptography RSA Laboratories Seminar Series

15. #5: Companion Technologies Hash functions Public-key infrastructure depends on Internet Desktop computing depends on Moore�s Law

16. RSA Signature Times, over Time(Illustrative)

17. #6: Standards Public-Key Cryptography Standards PKCS #1: RSA Encryption & Signatures PKCS #7: Cryptographic Message Syntax PKCS #11: Cryptographic Token Interface IETF PKIX, S/MIME

18. #7: Competition Diffie-Hellman algorithm (Cylink) Digital Signature Standard (NIST & NSA) Elliptic Curve Cryptography (Certicom)

19. #8: Application Secure e-mail? Signed documents? ? Encrypted Web transactions: Netscape SSL only server has a public key, at least initially

20. The Vision, Revised Secure communications for everyone via public-key cryptography, server-side first:

21. The Vision, Revised Secure communications for everyone via public-key cryptography, server-side first:

22. #9: Patience RC2 and RC4: Exportable ciphers Actually, the vision is being realized � the original technology was just a catalyst that got things started

23. #10: People R-S-A, especially Ron Rivest � founders Jim Bidzos � CEO Addison Fischer � lead investor Steve Duss�, Jeff Fassett, Ginny Kirkley, Kurt Stammberger, Jeff Thompson, Matt Robshaw, Yiqun Lisa Yin, Coni Garcia, Shari Oto and many more �

24. Summary of Lessons Learned Validation Partnership Product Marketing Companion technologies Standards Competition Application Patience People

25. Timeline 1976: Diffie-Hellman invented 1977: RSA invented 1982: RSA Data Security founded 1983: RSA patent issues 1991: RSA Laboratories launched 1991: PKCS documents published 1991: 1st RSA Conference 1994: Netscape introduces SSL 1995: VeriSign spun out of RSA Data Security 1996: Security Dynamics acquires RSA Data Security 1999: Security Dynamics renamed RSA Security 2000: RSA patent expires 2006: 15th RSA Conference, 1200+ employees, ~50 countries

26. Questions?

27. Contact Information Burt KaliskiChief Scientist, RSA LaboratoriesVice President of Research, RSA Securitybkaliski@rsasecurity.comhttp://www.rsasecurity.com/rsalabs