This Recommendation | International Standard provides Abstract Syntax Notation One (ASN.1) modules for usingcryptographic syntax in ITU-T Recommendations. Cryptographic message syntax (CMS) provides data integrity, confidentiality, origin authenticity, and non-repudiation services needed for reliable information exchange and for strong authentication. It also brings together a set of cryptographic key management techniques to support flexible key establishment mechanisms, such as constructive key management, key agreement, key exchange, and password-based encryption. These techniques can be used to prevent fraud, and to protect personally identifiable and other sensitive information. This Recommendation | International Standard supports digital signature, encryption, and signcryption techniques based on the public-key technology defined in the ITU-T X.500 series | ISO/IEC 9594 multipart standard. All of the standardized encoding rules for ASN.1 are supported.