In the world of digital signature we often hear about time stamp. But what exactly is it and how does it relate to .p7m files? In this guide we explain it simply.
What is timestamp
The timestamp (timestamp) is a sort of digital "stamp" that certifies the date and time in which a document was signed or existed. It is issued by an accredited body and gives the document a certain date, enforceable against third parties.
What is it for
The digital signature proves who signed and that the document has not been modified. The timestamp adds a third element: when. It is used when it is important to demonstrate that a document existed on a certain date — for example contracts, tenders, documents with legal deadlines.
Timestamp and .p7m file
A file signed in CAdES has the extension .p7m. When a timestamp is added to that signature, the file can have extensions like .p7m.tsd or contain the timestamp within it. In practice: first you sign (the .p7m is born), then you can "time stamp" it to give a certain date.
How to read a signed and marked document
To open and read the document contained in a signed file, with or without timestamp, use P7M Viewer:
1. Open the Open .p7m tool.
2. Upload the file.
3. View or download the original document, and see who signed it.
The complete legal verification of the brand (validity, issuing body) is done with dedicated tools; to read the content all you need is your browser.
Frequently asked questions
Is the timestamp mandatory? No, it is used when a certain date that can be enforced against third parties is needed.
How is this different from a signature? The signature says who and what; the timestamp tells you when.
Can I open a marked up file with P7M Viewer? Yes, open and read the document; It's free for a single file.
In summary
The timestamp gives certain date to a signed document, completing the digital signature that proves authorship and integrity. To read signed .p7m files, with or without branding, use P7M Viewer in seconds, for free.
