Enhance non qualified time stamps to interval qualified time stamps

In some cases it is desirable to be able to ”enhance self made time stamps” in a cost efficient manner, such that they provide a similar level of evidence as a qualified time stamp.

For example that might be the case if you are hosting your own Time Stamp Authority but at the same time you need a similar level of evidence as with a qualified time stamp authority.

A few qualified time stamps can be used to enhance an arbitrary number of self made time stamps with moderate computational cost.

This is mainly achieved by appropriately linking an arbitrary number of self made time stamps Si, issued at time ti, with two qualified time stamps issued at time T1 and T2 respectively, in a way that one is able to prove that T1 < ti < T.

The above results in interval qualified time stamps!

Obviously this is only one suggestion but there are many more ways. For example building hash trees and signing them.


Another way of enhancing non qualified time stamps is to publish the Time Token automatically to a blockchain to make sure issued time token cannot be altered retroactively.

Please read more here: http://www.timenotary.com/time-stamping-related-applications/blockchain_rfc3161/