Digital Signature

These techniques are designed to provide the digital counterpart to handwritten signatures and can be achieved using cryptography. In substance a digital signature of a message is a number dependent on some secret known only to the signer and on the content of the message being signed. Signatures must be verifiable without requiring access to the signer's secret information.

Digital signatures have many applications in information security, including authentication, data integrity and non-repudiation. One of the most significant applications of digital signatures is the certification of public keys in large networks.