The world of digital signature is full of acronyms: .p7m, CAdES, PAdES, PEC, SdI... In this glossary we explain in a simple way the most important terms you encounter with signed files.
.p7m
Extension of a digitally signed file in CAdES format (PKCS#7). Contains the original document plus the signature. It opens by extracting the document, for example with P7M Viewer.
CAdES
European digital signature standard based on PKCS#7 / CMS. Produces .p7m files. This applies to any type of document.
PAdES
Signature standard applied inside the PDF: the file remains a normal .pdf, openable anywhere, with the signature embedded.
PEC
Certified Electronic Mail: email with legal value that guarantees sending and delivery. Attachments are often signed .p7m files.
SdI
Interchange System of the Revenue Agency: the system through which electronic invoices pass. Requires digitally signed invoices.
Electronic invoice (XML)
The invoice in XML format defined by the Revenue Agency. When signed it becomes a .xml.p7m file.
Qualified certificate
The digital certificate, issued by an accredited body, which identifies the signatory and gives legal value to the signature.
Timestamp
A "stamp" that certifies date and time in which a document was signed or existed, useful for providing temporal certainty.
Multiple signature
A document with multiple digital signatures, parallel or nested (`.p7m.p7m` file).
How to open signed files
Whatever the term, to open a .p7m file all you need is P7M Viewer: upload the file and get the original document, for free and in a few seconds.
In summary
Knowing these terms — .p7m, CAdES, PAdES, PEC, SdI, qualified certificate, timestamp — helps you understand the digital signature. And to open signed files, P7M Viewer does the job in a snap.
