| 摘要 |
Methods and systems are described for enabling secure delivery of a content item from a content source to a content receiving device associated with a decryption module configured for use with a split-key cryptosystem comprising encryption and decryption algorithms E and D, a cipher algorithm for generating encryption and decryption keys e,d on the basis of secret information S and a split-key algorithm for splitting e and/or d into i different split-encryption keys e1, e2, . . . , ei and/or k different split-decryption keys d1, d2, . . . , dk respectively, such that Ddk(Ddk-1( . . . (Dd2(Dd1(Eei(Eei-1( . . . (Ee2(Ee1(X)) . . . ))=Ddk(Ddk-1( . . . (Dd2(Dd1(Xe1, e2, . . . , ei))=X wherein i,k≧1 and i+k>2, wherein the method comprises: provisioning said decryption module with first split-key information comprising at least a first split-key; generating second split-key information comprising at least a second split-key on the basis of said first split-key information, said decryption key d and, optionally, said secret information S; and, provisioning said decryption module with said at least second split-key 1 information for decrypting an encrypted content item Xe on the basis of said first and second split-key information and decryption algorithm D in said decryption module. |
| 主权项 |
1. Method for enabling secure delivery of a content item from a content source to a content receiving device, said content receiving device being associated with a decryption module and said decryption module being configured for use with a split-key cryptosystem comprising an encryption algorithm and a decryption algorithms, a cipher algorithm for generating encryption and decryption keys on the basis of secret information and a split-key algorithm for at least one of (i) splitting the encryption key into different split-encryption keys or (ii) splitting the decryption key into different split decryption keys;
the split-key cryptosystem further comprising a number of consecutive encryption and decryption operations, the method comprising: provisioning said decryption module with first split-key information comprising at least a first split-key; generating second split-key information comprising at least a second split-key on the basis of said first split-key information, said decryption key and, optionally, said secret information; and provisioning said decryption module with said at least second split-key information for decrypting an encrypted content item on the basis of said first and second split-key information and the decryption algorithm in said decryption module. |
