Cryptography is the science and study of secret writing. It is concerned with the ways in which information can be encoded to prevent disclosure. It is tied closely to two of the three basic pillars of security: integrity and confidentiality. Cryptography offers its users the capability to protect the confidentiality of information through eavesdropping or other interception techniques. Cryptography protects integrity by ensuring that only the individuals who have been authenticated and authorized can access and view the data. Cryptography provides integrity services by detecting the modification to, addition to, or deletion of data while in transit or in storage.
The CISSP candidate is expected to know basic information about cryptographic systems, such as symmetric algorithms, asymmetric algorithms, public key infrastructure, message digests, key management techniques, and alternatives to traditional cryptography, such as steganography.