XAdES / PAdES / CAdES

XAdES, PAdES, and CAdES are the three standard digital signature formats defined by ETSI for the eIDAS regulation. XAdES (XML Advanced Electronic Signatures, EN 319 132) signs XML documents, PAdES (PDF, EN 319 142) embeds the signature token directly in the PDF — this is the format Certyneo uses to produce offline-verifiable files in Acrobat Reader. CAdES (CMS, EN 319 122) applies to arbitrary binary streams. Each format comes in profiles (B-B, B-T, B-LT, B-LTA) offering increasing guarantees: validity over time, qualified timestamp, long-term archival proof.