Public Key Infrastructure (PKI) technology proven as the only technology available today that ensures non-forgeable signatures.
In a PKI system, each user has two keys: a public key and a private key. These keys can be used for encrypting and decrypting information, for digitally signing electronic information and for verifying the authenticity of their owner. While the public key is distributed widely, the corresponding private key is held by its owner in a secure place. While both keys are mathematically related, the public key cannot reveal the private key. This makes PKI a great technology for Digital Signatures.
The EU Directive 1999/93/EC for Digital Signatures recognised and defined a stronger type of electronic signature, the Advanced Electronic Signature. Only Public Key Infrastructure (PKI) digital signatures meet the requirements for such signatures. Advanced digital signatures provide not only stronger user authentication, but also protect the integrity of the data signed, thus ensuring non-repudiation of the transaction by the signer.