What is the GKP format?
GKP (Gankpo Package) is an open and documented file format that encapsulates an original document with its certification metadata, digital signature, and certified timestamp. It is the standard for creating tamper-proof electronic originals.
Secure
AES-256 encryption, ECDSA signature, and RFC 3161 timestamping for maximum security
Open
Public specifications, documented format, interoperable with all systems
Tamper-proof
Any modification of the content is immediately detected by cryptographic verification
Certified
eIDAS compliant qualified timestamping, probative value in court
Structure of a GKP file
1. Original document
The source file (PDF, image, video, CAD...) is encapsulated without modification in the GKP container
2. Metadata
Structured information: author, date, description, MIME type, SHA-256 fingerprint
3. Digital signature
ECDSA P-256 or RSA-2048 signature of the document and metadata by the author
4. Certified timestamp
RFC 3161 timestamp token issued by a certified authority (TSA) proving the exact creation date
Use cases
Intellectual Property
Protect your creations: artworks, designs, patents, trademarks. Prove anteriority in case of dispute.
Legal documents
Contracts, notarial acts, judgments. Guarantee authenticity and signature date.
Media and journalism
Photos, investigation videos. Fight against deepfakes and prove content origin.
Engineering and CAD
Technical plans, 3D models. Protect your industrial and architectural designs.
Public archives
Administrations, ministries. Ensure the integrity of official documents over the long term.
Scientific research
Experimental data, lab reports. Guarantee result traceability.