The ICertPassage Remote Protocol is a simple request-response pattern between the client and the server. The client MUST send the certificate request using one of the following ASN.1 DER encoded message formats:

• PKCS #10 as specified in [RFC2986].

• Cryptographic Message Syntax (CMS) as specified in [RFC3852].

• Certificate Management Messages over CMS (CMC) as specified in [RFC2797].

Details are as specified in [MS-WCCE] section 2.2.2.4. Each format contains a set of attributes and extensions describing the request.<3>