부인방지 기술

(출처 : wikipedia)
In law, non-repudiation implies one's intention to fulfill their obligations to a contract. It also implies that one party of a transaction cannot deny having received a transaction nor can the other party deny having sent a transaction. It is important to note that while technology such as cryptographic systems can assist in non-repudiation efforts, the concept is at its core a legal concept transcending the realm of technology. It is not, for instance, sufficient to show that the message matches a digital signature signed with the sender's private key, and thus only the sender could have sent the message and nobody else could have altered it in transit. The alleged sender could in return demonstrate that the digital signature algorithm is vulnerable or flawed, or allege or prove that his signing key has been compromised. The fault for these violations may or may not lie with the sender himself, and such assertions may or may not relieve the sender of liability, but the assertion would invalidate the claim that the signature necessarily proves authenticity and integrity and thus prevents repudiation.

법에서 부인방지는 접근시도에 대한 책임이다. 기술의 영역을 초월하는 법적개념이 핵심이다. 발신자만이 해당 메세지를 전송할 수 있고 어느누구도 전송과정에서 변경할 수 없어야 한다. 발신인이 디지털서명알고리즘의 결함을 주장할 수도 있지만 서명의 진위 역시 증명할 필요가 없게 되므로 부인은 방지된다.