초록 ▼

In a cryptographic communications system, a method and apparatus for allowing a sender of encrypted data to demonstrate to a receiver its ability to correctly generate key recovery information that is transmitted along with the encrypted data and from which law enforcement agents or others may recov

In a cryptographic communications system, a method and apparatus for allowing a sender of encrypted data to demonstrate to a receiver its ability to correctly generate key recovery information that is transmitted along with the encrypted data and from which law enforcement agents or others may recover the original encryption key. Initially, the sender generates a key pair comprising a private signature key and a corresponding public verification key and sends the latter to a key recovery validation service (KRVS). Upon a satisfactory demonstration by the sender of its ability to correctly generate key recovery information, the KRVS generates a certificate certifying the public verification key and the ability of the sender to correctly generate key recovery information. The sender uses its private signature key to generate a digital signature on the key recovery information, which is sent along with the key recovery information and encrypted data to the receiver. The receiver verifies the signature on the key recovery information using the certified public verification key and decrypts the encrypted data only if the signature is verified as being a valid signature.

대표청구항 ▼

[ What is claimed is:] [1.] In a communications system in which a first party transmits encrypted data along with recovery information to a second party who decrypts the encrypted data using a decryption key, said system having one or more key recovery agents for enabling recovery of said decryption

[ What is claimed is:] [1.] In a communications system in which a first party transmits encrypted data along with recovery information to a second party who decrypts the encrypted data using a decryption key, said system having one or more key recovery agents for enabling recovery of said decryption key using said recovery information, a method of demonstrating to said second party the ability of said first party to correctly generate said recovery information, comprising the steps of:having said first party generate a first key recovery block as a test block containing recovery information for a first decryption key and transmit said first key recovery block to an independent certification authority;having said independent certification authority validate said recovery information and, upon determining that said recovery information is correctly generated, generate a certificate certifying a public verification key corresponding to a private signature key of said first party;having said first party generate a second key recovery block containing recovery information for a second decryption key used by said second party to decrypt encrypted data received from said first party; andhaving said first party transmit said second key recovery block to said second party along with a digital signature generated on said second key recovery block using said private signature key to allow said second party to verify the ability of said first party to correctly generate the recovery information in said second key recovery block by validating said digital signature using said certificate.