Time stamp protocol

<p>The Time-Stamp Protocol, or TSP is a <a href="/facts/Cryptographic/e94PEVau">cryptographic</a> <a href="/facts/Protocol_(computing)/5uady7cB">protocol</a> for certifying <a href="/facts/Trusted_timestamping/eRjuYGTM">timestamps</a> using <a href="/facts/X.509/rs0JuYDd">X.509</a> certificates and <a href="/facts/Public_key_infrastructure/7fwMLxF4">public key infrastructure</a>.  The timestamp is the signer's assertion that a piece of electronic data existed at or before a particular time. The protocol is defined in <a href="/facts/RFC_(identifier)/esftTvE7">RFC</a> <a href="https://www.rfc-editor.org/rfc/rfc3161">3161</a>. One application of the protocol is to show that a <a href="/facts/Digital_signature/tY7e2pnW">digital signature</a> was issued before a point in time, for example before the corresponding certificate was revoked.
</p><p>The TSP protocol is an example of <a href="/facts/Trusted_timestamping/eRjuYGTM">trusted timestamping</a>. It has been extended to create the <a href="/facts/ANSI_ASC_X9.95_Standard/5F5vpfnT">ANSI ASC X9.95 Standard</a>.
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Time stamp protocol open-in-new

Time stamp protocol