The Certificate Management over CMS (CMC) is an internet standard by the IETF, defining transport mechanisms for the Cryptographic Message Syntax (CMS). It is defined in RFC 5272, its transport mechanisms in RFC 5273. It is one of two protocols utilizing the Certificate Request Message Format (CRMF), described in RFC 4211, with the other protocol being the Certificate Management Protocol (CMP).
References
Certificate Management over CMS Wikipedia(Text) CC BY-SA