Definitions of terms used when describing encryption of stored data.
plaintext – data in its original, intelligible form. Plaintext is not limited to string data, but is used to describe any data in its original representation.
ciphertext – data in an unintelligible form that preserves the information content of the plaintext form.
encryption – a reversible transformation of data from plaintext to ciphertext. Also known as enciphering.
decryption – the reverse transformation of ciphertext back to plaintext. Also known as deciphering.
key – a number used to encrypt or decrypt data. Symmetric-key encryption systems use the same key for both encryption and decryption. Asymmetric-key systems use one key for encryption and a different (but mathematically related) key for decryption. The SAP Sybase IQ interfaces accept character strings as keys.
Rijndael – pronounced “reign dahl.” A specific encryption algorithm that supports a variety of key and block sizes. The algorithm was designed to use simple whole-byte operations and thus is relatively easy to implement in software.
AES – the Advanced Encryption Standard, a FIPS-approved cryptographic algorithm for the protection of sensitive (but unclassified) electronic data. AES adopted the Rijndael algorithm with restrictions on the block sizes and key lengths. AES is the algorithm supported by SAP Sybase IQ.