Cybersecurity
Non-repudiation
Definition
Non-repudiation is the assurance that someone cannot deny the validity of something. It provides proof of the origin, integrity, and delivery of data. It is the concept of ensuring that a party in a dispute cannot repudiate, or refute the validity of a statement or contract.
Why It Matters
Non-repudiation is a critical legal and security concept. It provides undeniable proof that a specific action was taken by a specific entity, which is essential for digital signatures, financial transactions, and legal agreements.
Contextual Example
A digital signature provides non-repudiation. By signing a document with their private key, a person cannot later deny that they were the one who signed it, as they are the only one who should have access to that private key.
Common Misunderstandings
- Non-repudiation is one of the key services provided by public key cryptography, alongside confidentiality, authentication, and integrity.
- It is a stronger guarantee than simple authentication.