2. PUBLIC KEY CRYPTOSYSTEMS Symmetric Cryptosystems 6/05/2014 | pag. 2

3. ElGamal Encryption: Based on Diffie Hellman Key Exchange Cryptography 6/05/2014 | pag. 3 Security of Diffie Hellman key exchange not based on integer factoring (like RSA and Rabin) but on the discrete logarithm problem (DLP).

4. Discrete Logarithm Cryptography 6/05/2014 | pag. 4

5. Diffie Hellman Key Exchange Cryptography 6/05/2014 | pag. 5

6. Diffie Hellman Key Exchange Cryptography 6/05/2014 | pag. 6 Choose order g at least 2^160 to prevent Pohlig Hellman.

7. ElGamal Key Generation Cryptography 6/05/2014 | pag. 7

8. ElGamal Key Encryption Cryptography 6/05/2014 | pag. 8

9. ElGamal Key Decryption Cryptography 6/05/2014 | pag. 9

10. ElGamal Cryptography 6/05/2014 | pag. 10

11. ElGamal and Diffie Hellman Cryptography 6/05/2014 | pag. 11

12. HASH FUNCTIONS Symmetric Cryptosystems 6/05/2014 | pag. 12

13. Hash Function Cryptography 6/05/2014 | pag. 13

14. Compression Function Cryptography 6/05/2014 | pag. 14

15. One-way Function Cryptography 6/05/2014 | pag. 15

16. One-way Function Cryptography 6/05/2014 | pag. 16

17. Collisions Cryptography 6/05/2014 | pag. 17

18. Collisions Cryptography 6/05/2014 | pag. 18

19. Collisions Cryptography 6/05/2014 | pag. 19

20. Compression function from encryption functions Cryptography 6/05/2014 | pag. 20

21. Compression function from encryption functions Cryptography 6/05/2014 | pag. 21

22. Hash functions from compression functions Cryptography 6/05/2014 | pag. 22

23. SHA-1 Cryptography 6/05/2014 | pag. 23 3. The original length of x is written as a 64-bit number. 4. Append 3. to x from 2.

24. SHA-1 Cryptography 6/05/2014 | pag. 24

25. SHA-1 Cryptography 6/05/2014 | pag. 25

26. SHA-1 Cryptography 6/05/2014 | pag. 26

27. Message Authentication Codes Cryptography 6/05/2014 | pag. 27

28. Message Authentication Codes Cryptography 6/05/2014 | pag. 28

29. Message Authentication Codes Cryptography 6/05/2014 | pag. 29

30. Message Authentication Codes Cryptography 6/05/2014 | pag. 30

31. DIGITAL SIGNATURES & IDENTIFICATION Symmetric Cryptosystems 6/05/2014 | pag. 31

32. Digital Signatures Cryptography 6/05/2014 | pag. 32

33. RSA Signatures Cryptography 6/05/2014 | pag. 33 Key Generation:

34. RSA Signatures Cryptography 6/05/2014 | pag. 34 Signature Generation:

35. RSA Signatures Cryptography 6/05/2014 | pag. 35 Signature Verification:

36. RSA Signatures Cryptography 6/05/2014 | pag. 36

37. RSA Signatures with Hash Functions Cryptography 6/05/2014 | pag. 37

38. Other Public Key Digital Signatures Cryptography 6/05/2014 | pag. 38

39. ElGamal Signatures Cryptography 6/05/2014 | pag. 39 Key Generation:

40. ElGamal Signatures Cryptography 6/05/2014 | pag. 40 Signature Generation:

41. Cryptography 6/05/2014 | pag. 41 Signature Verification: ElGamal Signatures

42. Cryptography 6/05/2014 | pag. 42

43. Identification Cryptography 6/05/2014 | pag. 43

44. Identification Cryptography 6/05/2014 | pag. 44 One can use for example Passwords Challenge-Response identification based on symmetric encryption public key encryption Zero-knowledge proofs

45. MULTIMEDIA: CRYPTO IS NOT ENOUGH Symmetric Cryptosystems 6/05/2014 | pag. 45