1. Computer encryption is… Based on the science of cryptography

2. Encryption Padlock Analogy Anybody can lock a padlock… but, it takes a key to unlock it!

3. Symmetric key encryption In encryption, the word symmetric means those cases where the same key both encrypts and decrypts.

4. Asymmetric key encryption Type of encryption in which an encryption key (the public key) is used to encrypt a message, and another encryption key (the private key) is used to decrypt the message.

5. Public Key Security SSL TLS (Secure Sockets Layer) (Transport Layer Security) (Secure Sockets Layer) (Transport Layer Security)

6. Other Security Tools Checksum Checksum CRC (Cyclic Redundancy Check) CRC (Cyclic Redundancy Check) If a single character in the data is changed, then the data has been corrupted. Checksum or CRC e4d909c290d0fb1ca068ffaddf22cbd0 35d91262b3c3ec8841b54169588c97f7 Not identical Checksum or CRC

7. Ciphers or codes = algorithms. Most cryptography used today relies on computers because of the speed and security computers provide in cracking codes.

8. Hashing Algorithm Alice Bob Alice Bob Alice Bob Alice Bob Alice + + = Different Color + + + + = Same Color One-way function* *Example of two- way mathematical function = light switch.

9. Encryption + Authentication Passwords Passwords Pass cards Pass cards Digital Signatures Digital Signatures Fingerprint scan Fingerprint scan Retina scan Retina scan Face Scan Face Scan Voice identification Voice identification

10. Why do we need encryption? Credit-card information Social Security numbers Private correspondence Personal details Sensitive school information Bank-account information

11. But wait…there’s more! http://btwikilmc.pbworks.com/Encryption http://www.aptv.org/aptplus/