Method and apparatus for providing secure time stamps for documents and computer files

In a notarial time stamp generation apparatus, a method for generating time stamps, the method comprising the steps of:

• (a) receiving a request for generation of a notary time stamp;
• (b) retrieving a time signal, the time signal generated externally of the apparatus and comprising date and time data;
• (c) each time a request for generation of a notary time stamp is received, irreversibly modifying the output signature of a write once memory device to generate a unique time stamp identifier for each notary time stamp;
• (d) generating a notary time stamp from the date and time data and the time stamp identifier;
• and
• (e) generating as part of the notary time stamp a check-sum having a value derived from at least a portion of the notary time stamp.

An apparatus for generating notary time stamps comprising:

• means for retrieving a time signal, the time signal generated externally to the apparatus and comprising date and time data;
• program logic configured to irreversibly create a sequential time stamp identifier which is unique to each notary time stamp for association with the date and time data, said program logic comprising a memory device having a plurality of cells, each cell of which can be programmed only once and program logic that programs at least one cell each time a notary time stamp is generated;
• and
• program logic, responsive to the sequential identifier and the date and time data, and configured to generate a notary time stamp, the notary time stamp having a second portion comprising the sequential time stamp identifier, the date data, and the time data, and a first portion which may be utilized to verify the contents of the second portion of the notary time stamp.