What is signature anchoring?

Signing a file using a Ledger Nano S on Woleet’s platform

To address this limitation, and allow a new set of use cases, Woleet proposes an evolution of data anchoring: signature anchoring on Bitcoin. The functionality is already available on the Woleet platform and the specification is open (described here and in the Woleet API documentation). Anybody is free to implement a similar functionality in a different way, but of course everyone would benefit from a standardization and interoperability of proofs of signature (which is the case for Chainpoint based proofs of existence).

The process of signature anchoring is actually similar to data anchoring, except it creates a timestamped proof of signature of the data. With such a proof, not only you can prove that some data existed at a given point in time, but additionally that it was signed by an actor (eg. the creator of the data of any other actor wanting to « put its stamp » on the data).

The same data can be signed by any number of actors, at any point in time. Each signature generate a new proof and never modify the source data. This allow for a set of new use cases:

Remote signing of documents

one can send a file to a set of signees and ask them for a proof of signature: the file doesn’t need to follow a workflow and is never tampered

Signature timestamping with no intermediate

legacy signature solutions are either not timestamped, or use a centralized authority to prove signature timestamp, while timestamping is inherent to signature anchoring

Data provenance verification

— IoT sensors can emit data along with a signature proof to prove data origin and creation time

— schools can certify the diploma they deliver

— e-document used as proof of residence (like utility bills) can be signed by their emitter to eradicate forgery

Data certification verification

within a data processing workflow, a certification authority can sign some data to prove it certified it at a given date