Electronic Code Book (ECB) Native encryption mode that is used for small amounts of data. ECB is the weakest form of DES.
Cipher Block Chaining (CBC) Works by taking each data from the previous and applying it to the next.
Cipher Feedback Mode (CFB) Emulates a stream cipher and can be used when the encryption of individual characters is required.
Output Feedback Mode (OFB) Also emulates a stream cipher and generates random binary bits that are combined with the plain text to create cipher text.
Certificate Authority (CA) Used to verify and issue digital certificates. The certificate includes the public key and information about it.
Registration Authority (RA) Verifies authenticity for the CA.
Repository Accepts certificates and distributes them to authorized parties.
Archive Responsible for the long-term storage of archived information distributed from the CA.