Current Encryption Methods in Distributed Systems

1. Current Encryption Methods in Distributed Systems Meg Lindsay

2. What is Encryption? • The process of converting information or data into a code, especially to prevent unauthorized access • Plaintext is converted into ciphertext using an encryption algorithm and encryption key • Most important automated tool for network security • Primary purpose is to protect the confidentiality of digital data stored on computer systems or transmitted via the internet or any other computer network

3. Why is it important? 1. Internet privacy concerns are real 2. Hacking is big business 3. Regulations demand it

4. The Two Methods of Encryption • Symmetric method, also known as private key cryptography • Asymmetric method, also known as public key cryptography

5. Symmetric Method Sender encrypts the data with one key, sends the data (the ciphertext) and then the receiver uses the key to decrypt the data

6. Asymmetric Method A public key is freely available to everyone and is used to encrypt messages, and a different, private key is used by the recipient to decrypt messages

7. Encryption Location

8. Link-level Security • Each link is equipped on both ends with an encryption device • Provides high level of security, as all traffic over all communications links is secured • Requires large number of encryption devices in a large network • Message must be decrypted each time it enters a PSN/router because the node must read the VC number in the packet header to route the packet

9. End-to-end Encryption • Encryption process is carried out at two end systems • Source host encrypts data, data is transmitted in encrypted form • Destination shares a key with the source and so is able to decrypt the data • More secure against attacks on links and switches • Source cannot encrypt entire packet because the packet-switching node wouldn’t be able to read the header → can only encrypt actual data

10. 5 Common Encryption Algorithms

11. Triple DES • Symmetric algorithm • Developed to replace DES (Data Encryption Standard) • Effective key length of 112 bits • Slowly being phased out ciphertext = EK3(DK2(EK1(plaintext)))

12. Blowfish • Symmetric algorithm • Also designed to replace DES • Messages split into blocks of 64 bits and encrypted individually • Known for speed and overall effectiveness • One of the more flexible encryption methods available

13. Twofish • Symmetric algorithm • Blowfish’s successor • Block size of 128 bits, and keys may be up to 256 bits in length • Regarded as one of the fastest of its kind • Ideal for use in both hardware and software environments

14. Advanced Encryption Standard (AES) • Symmetric algorithm • Extremely efficient in 128 bit form, but also uses keys of 192 and 256 bits for heavy duty encryption purposes • Trusted as the standard by the US government and numerous organizations • Considered “impervious” to all attacks except brute force, which attempts to decipher messages using all possible combinations in the 128, 192 or 256 bit cipher

15. RSA • Asymmetric algorithm • Standard for encrypting data sent over the internet • The result of RSA encryption takes attackers quite a bit of time and processing power to break Encryption: C = me (mod n) Decryption: Cd = (me)d = m (mod n)

16. ...Questions?