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Questions tagged [timestamping]

Generally, a timestamp is the current time of an event that is recorded by a computer. You can use digital timestamps via a trusted authority to certify and protect your intellectual property or your records integrity.

Generally, a timestamp is the current time of an event that is recorded by a computer. You can use digital timestamps via a trusted authority to certify and protect your intellectual property or your records integrity.

A special form of timestamping is called "trusted timestamping", which is described in RFC 3161. A "trusted timestamp" is a timestamp issued by a trusted third party (TTP) acting as a Time Stamping Authority (TSA). It is used to prove the existence of certain data before a certain point without the possibility that the owner can backdate the timestamps.

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Can timestamping provide evidence of absence before a certain time?

Normally trusted timestamping proves that certain information existed at or before a certain time. However, sometimes there is a need to prove the opposite; that something did not exist before a certain time. Consider that I want to prove by…
Tobias Bengtsson
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Is there a digital time-stamping scheme that does not rely on a time-stamping authority?

Given a bit string, is it possible to assign it an immutable time stamp that is verifiable as correct without assuming a (one or more) trusted time-stamping authority? A time-stamp is correct if it is within delta milliseconds of the creation of the…
Swapnil Bhatia
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Why do key exchange protocols need secure clock synchronization?

I'm studying Kerberos and other Key Exchange Protocols. They always (or very often) require that the clocks are synchronized. To this purpose they periodically probe a time-server. This is said to be a critical operation because new kind of attacks…
Luigi2405
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How truncated timestamps are used?

Consider the following setting: We have a sender $\textbf{A}$ and a receiver $\textbf{B}$. The sender $\textbf{A}$ a wants to send a message $M$ through a channel where each message to $\textbf{B}$ can be up to 8 bytes. Due to the limited size each…
user35869
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Timestamping services authorities, utilizing Linked, hybrid and other than PKI schemes

What are well respected Cryptographic Timestamping authorities utilizing more sophisticated than just PKI (RFC 3161) schemes, like Linked, Linked and signed, distributed hash trees (maybe P2P?), hybrid ? Is there any good resource (better than…
Grzegorz Wierzowiecki
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Is timestamping possible without publishing?

The Wikipedia article Trusted Timestamping states that we can timestamp data by publishing it's hash. Publishing can be done either independently or via a third-party publisher, as explained by DrLector on another thread. However, can we timestamp…
Pacerier
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