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The Time-Stamp Protocol, or TSP is a cryptographic protocol for certifying timestamps using X.509 certificates and public key infrastructure. The timestamp is the signer's assertion that a piece of electronic data existed at or before a particular time.
Trusted timestamping is the process of securely keeping track of the creation and modification time of a document. Security here means that no one—not even the owner of the document—should be able to change it once it has been recorded provided that the timestamper's integrity is never compromised.
For example, a broadcast encoder might insert a watermark every few seconds that could be used to identify the broadcast channel, program ID, and time stamp. This watermark is normally inaudible or invisible to the users, but is detectable by display devices like phones or tablets which can read the watermarks to identify the content it is ...
The term "timestamp" derives from rubber stamps used in offices to stamp the current date, and sometimes time, in ink on paper documents, to record when the document was received. Common examples of this type of timestamp are a postmark on a letter or the "in" and "out" times on a time card .
Yellow dots on white paper, produced by color laser printer (enlarged, dot diameter about 0.1 mm) Printer tracking dots, also known as printer steganography, DocuColor tracking dots, yellow dots, secret dots, or a machine identification code (MIC), is a digital watermark which many color laser printers and photocopiers produce on every printed page that identifies the specific device that was ...
A subscriber, with knowledge of the watermark and how it is recovered, can determine (to a certain extent) whether significant changes have occurred within the data file. Depending on the specific method used, recovery of the embedded auxiliary data can be robust to post-processing (such as lossy compression ).
In computing, timestamping refers to the use of an electronic timestamp to provide a temporal order among a set of events.. Timestamping techniques are used in a variety of computing fields, from network management and computer security to concurrency control.
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