What a trusted timestamp proves, and what it does not

Proving when something existed sounds simple until a dispute starts. The date on a document, a photo or an export is usually written by the device that made it, from a clock its owner can change, so it shows when the device claims an event happened, not when it did. A trusted timestamp is the opposite: a record of time issued by something the person holding the file cannot set.

This post explains what a timestamp actually is, what makes one trustworthy, how a server timestamp and a qualified timestamp differ, and precisely what the server timestamp Danaya binds at capture does and does not prove.

Why the date in a file is not a timestamp you can trust

A file's date lives in editable metadata written by the device, and free tools rewrite it in seconds. Set the clock back and every photo taken after carries the earlier date; export a report and the filename or modified date is just another label anyone can change. None of it is tied to the content or vouched for by an independent party, so it cannot settle when something was really created.

A real timestamp has to come from outside the sender's control and be bound to the exact content it dates. The useful question is not what time the file says, but who issued that time, and whether the file can be altered afterward without the timestamp breaking.

What makes a timestamp trustworthy: server and qualified

A server timestamp is issued by a server at the moment it receives a fingerprint of the file, and signed, so the time comes from the server rather than the device clock and cannot be set by the sender. Because it is bound to a cryptographic fingerprint of the content, any later edit breaks the match, which is what makes it evidence rather than a note.

A qualified timestamp goes a step further: under the EU eIDAS regulation, a qualified trust service provider issues it under audited conditions, which gives it the strongest legal standing for proving a datum existed at a point in time. These are different tiers: a server timestamp is strong, verifiable and practical, while a qualified eIDAS timestamp is the regulated gold standard. Knowing which you have matters before you lean on it in a dispute.

What Danaya's timestamp proves, and what it does not

When a photo or video is captured live, Danaya computes a SHA-256 fingerprint of the file and binds it to a server timestamp and the GPS position, signed with an HMAC. That proves the exact file was registered at the server at that time, independent of the device clock, and that it has not been altered since, because any edit breaks the fingerprint. Anyone can confirm it from a public verification link, with no account.

Being precise about the limits: this is a server timestamp, not a qualified eIDAS timestamp from a trust service provider, so it is strong verifiable evidence rather than a regulated qualified timestamp. It fixes when the capture reached the server, and the GPS position is declarative, read from the capturing device, so treat it as a strong indication of place. Capture is live only, which is why an imported or AI-generated file cannot earn a valid timestamped seal in the first place.

FAQ

Can the date shown on a photo prove when it was taken?

No. That date comes from the device clock, which anyone can set, so it shows when the device claims the shot happened, not when it did. Only a timestamp issued by something the sender cannot control, like a server timestamp, fixes the real time.

What is a trusted timestamp?

A record of time issued by a party the file holder does not control, bound to a fingerprint of the content. Because the time is not set by the sender and any later edit breaks the binding, it can prove a specific file existed at a point in time.

Is Danaya's timestamp an eIDAS qualified timestamp?

No. Danaya binds a server timestamp to the file's SHA-256 fingerprint at capture and signs it, which is strong, publicly verifiable evidence. It is not a qualified timestamp issued by an eIDAS trust service provider, which is a separate regulated tier.

Does a timestamp prove where a photo was taken?

A timestamp proves when, not where. Danaya also records a GPS position at capture, but that position is declarative, read from the capturing device, so read it as a strong indication of place rather than a hardware-attested fact.

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