Patent ID: 8327150

Claim:
A method implemented on a computer for providing a time certification signature certifying that a set of information existed at an observation time, the method comprising: acquiring the set of information to be certified; acquiring identity data configured to identify the set of information; receiving at said computer first observation data associated with the observation time, the first observation data being sent to said computer from a first external server via Internet; receiving second observation data sent to said computer, the second observation data being sent from a second external server via the Internet to said computer; using the first observation data and the second observation data to generate time certification data for said observation time; generating, by the computer, the time certification signature for said observation time by encrypting with an encryption key the observation time, the identity data and the time certification data, wherein the encryption key is configured for use in decrypting the time certification signature for determination of the observation time; and attaching the time certification signature to the set of information to certify that the set of information existed at said observation time; wherein the first observation data is generated for said observation time from observation of either measurements or image data for a target object that changes without repeatability as time elapses.