⁦G.⁩ Sigelith: time proofs

Creating a time proof for a single file

Why

Sometimes you need to show someone a single file from the backup, for example a contract or a project, and demonstrate that it already existed in this form at the moment the version was timestamped. A file proof confirms this one file and does not reveal any other files in the backup.

Before you start

  • The file must lie in a version timestamped with Sigelith by version 3.0 of the program or newer (see “Timestamping backup versions with Sigelith”).
  • The version's seal must have the week's signature, that is, be “signed”.

Step by step

  1. In the menu on the left, click “Browse”, choose the backup folder and click “Open”.
  2. Find the file and select it (see “Finding a file in the backup and browsing its versions”).
  3. Click “Time proof…”.
  4. The program asks whether to include the file's path in the backup in the proof:
    • “Yes”: the proof also shows where the file was;
    • “No”: the proof still confirms the file and the moment of timestamping, but without the path;
    • “Cancel”: nothing is created.
  5. Choose where to save the proof and click “Save”.

What you should see

Two files: the proof, ending in .sigelith-proof, and next to it a PDF certificate. Below the file list, “Saved the proof and PDF certificate: …” appears.

What next

  • The recipient needs the file and the proof; the PDF certificate makes it easier to read. Sigelith Desktop or the sigelith.org/verify/ page can check them.
  • The proof fits only the same bytes. A file that has been opened and saved again no longer matches it, so pass on the file saved from the backup with the “Save as…” button.
  • The proof comes from the version in which the saved copy of the file lies. A file unchanged for a long time lies in an older version, so the proof shows an earlier moment.

If something goes wrong

  • “This version has no seal for individual files (a backup made before version 3.0 or without timestamps).”: the version was made without timestamping or with an older program. A file proof can be made only from a timestamped version.
  • “This version's seal is still waiting for the Sigelith weekly signature”: after Monday 00:00 UTC, make a backup with timestamping or click “Refresh online” in the “Timestamps” window, and try again.
  • “The version list was changed after it was timestamped.” or “The version's file tree does not match the seal.”: the version in the backup does not match its seal. See “Checking that nobody has tampered with files in the backup”.