1. PGP Encryption Justin Shelby

2. Encryption Methods  There are two basic key types for cryptography Symmetric Asymmetric

3. Symmetric Key Cryptosystems  One key is used to both encrypt and decrypt messages  Much more widely used than asymmetric.  Must use an alternate transfer method to spread the key.

4. Asymmetric Key Cryptography  Also called public key encryption.  Uses two keys, one public, the other private.  Can freely transmit the public key.  VERY slow. Approximately10,000 times slower than symmetric.

5. Why bother?  Financial information  Medical information  Military secrets  Privacy

6. Background of PGP  Pretty Good Privacy  Created by Phil Zimmerman in 1991  No license required for non-commercial use  Rapidly spread across the internet

7. Background Continued  Criminal investigation started for export of munitions due to using a key larger than 40 bits.  Eventually dropped and regulations relaxed.  Created the OpenPGP standard for interoperability.  Free Software Foundation created GPG GNU Privacy Guard

8. How PGP Works  Compresses the message or file  Generates a symmetric key  Encrypts the compressed message  Encrypts the symmetric key with the recipients public key  Signs the compressed and encrypted file with one of PGP’s hash functions

9. Program functions  Encrypted emails and instant messages  Creation of an encrypted virtual partition  Encrypt the hard drive Must enter passphrase to access it, even to boot up the machine.  Secure shared folder  File shredder

10. Algorithms  Asymmetric RSA DSS/DH  Symmetric AES CAST TripleDES IDEA Twofish  Hashes SHA-2  256, 384, and 512 bits RIPEMD-160 SHA-1 MD-5

11. PGP Setup  Download the software from the website www.pgp.com Current version 9.61  Run the setup program and reboot  Enter your information

12. PGP Setup Continued  Select your preferred key type  Enter your passphrase and generate your key

13. Is it Secure?  “If all the personal computers in the world – 260 million – were put to work on a single PGP-encrypted message, it would still take an estimated 12 million times the age of the universe, on average, to break a single message William Crowell, Deputy Director of the NSA March 20, 1997

14. Questions?

15. Sources  http://www.wikipedia.org http://www.wikipedia.org  PGP Desktop 9.6 help pages  http://cpsc420.cs.clemson.edu http://cpsc420.cs.clemson.edu  http://www.mccune.cc http://www.mccune.cc