Patent ID: 7039816

Claim:
A method for using a removable cryptographic module to enable a second device to obtain secure access to encrypted compressed digital video content, comprising: (a) receiving a rights enablement datum and a key derivation datum into said removable cryptographic module, where (i) said rights enablement datum includes an encrypted representation of a key enabling decryption of said key derivation datum, and (ii) said key derivation datum includes an encrypted representation of a key enabling said second device to decrypt said encrypted content; (b) said cryptographic module transforming said rights enablement datum, using a key stored in said cryptographic module, to determine said key enabling decryption of said key derivation datum; (c) said cryptographic module transforming said key derivation datum, using said key enabling decryption of said key derivation datum, to determine an initial content decryption key; (d) said cryptographic module re-encrypting said initial content decryption key to produce a re-encrypted content decryption key datum, where: (i) said re-encrypted key datum enables said second device to decrypt said encrypted compressed digital video content, and (ii) said re-encrypting is secured by a public key corresponding to said second device; and (e) transmitting said re-encrypted content decryption key datum to said second device.