Notes on the Timestamp Server

The solution to the transaction history problem begins with a timestamp server.

Satoshi explains a timestamp server takes a hash of a block of items to be timestamped and widely publishes it such as in a newspaper or Usenet post.

Usenet was a popular online forum in the 1990s, like Twitter or Facebook now.

A timestamp proves that the data must have existed at the time to get the hash.

Every timestamp includes the previous timestamp in its hash forming a chain.

NOTES

Using cryptographic hashes to timestamp data wasn't a new idea.

In fact, a Florida based company had been using cryptography and timestamping to purchase ads in the New York times as early as 1995! They were found in the "Notices and Lost & Found" section of the paper.

The wide distribution of the paper made it nearly impossible to alter already published timestamps as you would have to find and replace all copies of the New York Times!

Remember, Satoshi mentioning Usenet and newspapers was just a way to aid the explanation of publicly broadcasting timestamps.

The main focus is the chain of timestamps, not the publishing mechanism.

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