Dating an electronic file to the second and guaranteeing its existence and integrity using time stamp tokens.
The legal value of time stamping
A time stamp token has legal value from the moment it is issued by a Time Stamping Authority in accordance with the standardised technical and legal protocols governing time stamping services.
The time stamp token, like the binding force of a postmark, protects against any dispute about the contents of a file or the date it was issued or received. It certifies that a file has not been altered between the date it was time stamped and the date it is checked.
Uses of time stamping
All-digital processes lead to varied and frequent uses of time stamping as proof of:
– An archive or a contract etc. not having been altered
– Compliance with legal deadlines for withdrawal or for a contract to take effect (insurance, membership credit etc.)
– Prior claim: submission to a call for tender, patent application etc.
– Enforceable acknowledgements of receipt, notices to comply, contract cancellations/renewals etc.
– Traceability of actions, regulatory requirements such as Basel II, SOX etc.
– Electronic invoicing, due to the obligation to be able to guarantee the authenticity, integrity and permanence of electronic invoices (Bulletin Officiel des Impôts 3 E-107 of 11 January 2007)
Technical principles of time stamp tokens
The time stamp token is a file resulting from the association between the hash value computed from the time stamped data and a date and time from a reliable time source, the whole signed electronically by the Time Stamping Authority.
As each document has a unique hash value, comparing a file with a hash to ensure that they match perfectly tells us that the file already existed in its current form on the date of the token. The Time Stamping Authority’s electronic signature seals the token, preventing its intentional modification.
For each time stamp request, a token is associated with the file to be time stamped.
Examples of use :
– Dating graphical or intellectual creations
– Validating the time when an electronic message is sent or received
– Time stamping payslips
– Closing an electronic auction
– Dating the acceptance of terms and conditions when a purchase is made on the web
– Digitally sealing documents before archiving
– Ensuring traceability of actions to meet regulatory requirements such as Basel II, SOX etc.