Closed Source

SVG icon: 

Verifiable Document Redacting

A verifiable document redacting primitive that empowers cloud users to easily remove some part of their already signed document without having an impact on the validity of the signature. Thanks to this new primitive, users will not disclose private information of the document that does not need to be shared with the destined party.

Authenticated Encryption

Authenticated encryption with new security model and construction. StoA authenticated encryption with variable stretch is vulnerable to some attacks that misuse the variable stretch. A new security definition is proposed and followed by a new construction.

Shared Ownership

Shared Ownership allows joint access control decisions on collaboratively created cloud data. In our work we present an instantiation of shared ownership that is more efficient than previous work and allows fair accounting through block-chains.


Proofs of retrievability for data replications. It allows the data replication be handled by the cloud provider, who will then generate proofs of retrievability of these replicas upon user attestation.


De-duplication on the authenticators used for Proofs of Retrievability across multiple users. Relying on key-message homomorphic encryption, the cloud providers are able to merge the PoR authenticators generated by different users using different credentials and the merged authenticators is verifiable by all users.

Secure Deletion

The primitive provides secure deletion on an honest-but-curious cloud storage. Therefore, clients can store all the files on the cloud as usual, but still achieve secure deletion, which cannot be guaranteed otherwise. The solution is based on encryption.

TPM-based Remote Attestation (TRAVIS)

Remote Attestation is the activity of making a claim about properties of a target by supplying evidence to an appraiser over a network. The Remote Attestation generates the evidence of whether or not the untrusted cloud platform is running in the expected state, and therefore, the result of the service, application or VM image outsourced to the cloud is trustworthy.