摘要 |
In order to facilitate access to encrypted broadcast or multicast data an encrypted service key is sent from an access server of the communication network to the user terminal, passing the encrypted service key to a secure module of the user terminal. The secure module has access to a decryption key for decrypting the encrypted service key but this decryption key is inaccessible to other functions of the user terminal. Acknowledgement of receipt of the service key at said secure module, and sending the acknowledgement from the user equipment to the access server; authenticating the receipt at the access server and sending a return acknowledgement from the access server to the user terminal, and passing the return acknowledgement to the secure module; and authenticating the return acknowledgement at the secure module, and subsequently making the decrypted service key available to the user terminal, the service key making possible directly or indirectly the decryption of broadcast and/or multicast data. |