digitaalallkiri

Digitaalallkiri is a cryptographic method used to sign electronic data in order to verify the signer's identity, ensure data integrity, and provide non-repudiation. A digital signature is created by applying the signer’s private key to the data (typically after hashing) and is bound to a digital certificate that identifies the signer and links the key to a trusted authority.

How it works: The signer uses a private key stored securely in a hardware token, smart card, or a secure mobile app. The corresponding public key and certificate are distributed so others can verify the signature by checking the cryptographic signature against the data and the issuer's certificate. The system can also include timestamping and certificate revocation checks to bolster trust.

Legal framework and types: in the European Union, electronic signatures are categorized as simple electronic signatures, advanced electronic signatures, and qualified electronic signatures (QES). A QES, created by a trusted service provider with a qualified certificate, has the same legal effect as a handwritten signature under the eIDAS Regulation. Many jurisdictions, including Estonia, rely on PKI-based digital signatures for official documents and e-governance.

Uses and benefits: digital signatures enable legally binding agreements, secure document workflows, and efficient remote transactions. Advantages include authenticity, integrity, speed, and lower administrative costs, while challenges involve secure key management, protection of private keys, reliance on trusted issuers, and ensuring cross-border interoperability.

Notes: The term digitaalallkiri is most commonly used in Estonian-language contexts and reflects the broader concept of digital signatures used worldwide.