CAd ES (computing) - Profiles

Profiles

CAdES defines six profiles (forms) differing in protection level offered. Each profile includes and extends the previous one:

• CAdES, basic form just satisfying Directive legal requirements for advanced signature;
• CAdES-T (timestamp), adding timestamp field to protect against repudiation;
• CAdES-C (complete), adding references to verification data (certificates and revocation lists) to the signed documents to allow off-line verification and verification in future (but not storing actual verification data);
• CAdES-X (extended), adding timestamps on the references introduced by CAdES-C to protect against possible compromise of certificates in chain in future;
• CAdES-X-L (extended long-term), adding actual certificates and revocation lists to the signed document to allow verification in future even if their original source is not available;
• CAdES-A (archival), adding possibility for periodical timestamping (e.g. each year) of the archived document to prevent compromise caused by weakening signature during long-time storage period.