How strong is the encryption used in the UCSB VPN service?
The UCSB VPN service uses AES (Advanced Encryption Standard) with a key length of 256 bits. The National Institute of Standards and Technology (NIST) has created AES, which is a new Federal Information Processing Standard (FIPS) publication that describes an encryption method. AES is a privacy transform for IPSec and Internet Key Exchange (IKE) and has been developed to replace the Data Encryption Standard (DES). AES is designed to be more secure than DES: AES offers a larger key size, while ensuring that the only known approach to decrypt a message is for an intruder to try every possible key. It also uses a technique called Cypher Block Chaining (CBC) in which each plaintext block is XORed with the previous cypher text block before encryption. This makes dictionary style attacks very difficult and increases the overall effectiveness of encryption.
