초록 ▼

A signer uses an undeniable signature scheme to sign his public key to thereby create an "undeniable certificate" which can be used to verify the signer's digital signature on any message signed using the signer's corresponding private key. Hence, once the undeniable certificate is received by the r

A signer uses an undeniable signature scheme to sign his public key to thereby create an "undeniable certificate" which can be used to verify the signer's digital signature on any message signed using the signer's corresponding private key. Hence, once the undeniable certificate is received by the recipient, the recipient and the signer engage one time in a confirmation protocol or denial protocol to the satisfaction of the recipient that the undeniable certificate has in fact been signed by the signer thus certifying signer's public key. Thereafter, the recipient can use the certified public key to verify any documents signed by the signer with no further interaction with the signer. However, third parties are precluded from verifying the signer's signature since they do not possess the confirmed undeniable certificate and corresponding public key. Digital signatures can now be verified between two parties using a public key as in traditional digital signatures but which avoids verifiability by third parties.

대표청구항 ▼

[ We claim:] [1.]1. A method for generating an undeniable certificate from a signer to a recipient wherein said signer sends said undeniable certificate thereby eliminating the need for a trusted third partly, said method comprising the steps of:generating a first key pair for an undeniable signatur

[ We claim:] [1.]1. A method for generating an undeniable certificate from a signer to a recipient wherein said signer sends said undeniable certificate thereby eliminating the need for a trusted third partly, said method comprising the steps of:generating a first key pair for an undeniable signature scheme comprising a first private signing key and a corresponding first public verification key, said first public vertification key for verifying undeniable signatures generated under the first private signing key,generating a second key pair for a digital signature scheme comprising a second private signing key and a corresponding second public verification key, said second public verification key for verifying a signature on a message generated with the second private signing key;signing said second public verification key by the signer using the first undeniable private signing key to generate an undeniable certificate of the second public verification key;sending to the recipient said undeniable certificate of the second public verification key; andinteracting in a confirmation protocol between said signer and said recipient, said signer needing no prior knowledge of said recipient, using the first undeniable public verification key to verify to the recipient that said undeniable certificate was signed using the first undeniable provide signing key, said recipient accepting or rejecting said undeniable certificate.