Method, system and terminal apparatus for enabling content to be reproduced in multiple terminals

A system for reproducing equal content in at least one terminal by generally authenticating a service provider, a terminal and a User Identity Module (UIM), the system comprising:

• the service provider for performing authentication for the terminal and the UIM, performing a registration process for allowing the UIM to be used in said at least one terminal, reporting results for a service join request from the UIM through the terminal, and encrypting and providing corresponding content in service joining;
• the terminal for transferring a message exchanged between the service provider and the UIM, acquiring a shared encryption key with the UIM through the authentication, and decrypting and reproducing the encrypted content, which is provided according to the service joining, utilizing the shared encryption key;
• and
• the UIM for acquiring both the shared encryption key with the terminal and a shared session key with the service provider through the authentication, and providing the terminal with an encryption key for decrypting the encrypted content.

A terminal apparatus for reproducing equal content in at least one terminal by generally authenticating a service provider, a terminal and a User Identity Module (UIM), the terminal apparatus comprising:

• a Digital Rights Management (DRM) module for managing registration, service joining, and use of content;
• a communication module for receiving a message from the service provider, and transmitting a response message to the service provider in response to reception of the message;
• an interface module for transferring the message received through the communication module to the UIM, and receiving a response message corresponding to the transferred message from the UIM;
• and
• an authentication module for acquiring a shared encryption key with the UIM by performing authentication for the UIM, and decrypting encrypted content, which is provided according to the service joining, utilizing the shared encryption key.

A content reproduction method in a system for reproducing equal content in at least one terminal by generally authenticating a service provider, a terminal and a User Identity Module (UIM), the content reproduction method comprising the steps of:

• acquiring, by the terminal, a second encryption key KUT between the terminal and the UIM from an authentication message including a procedure for encrypting the second encryption key KUT with a first encryption key KT between the terminal and the service provider, by using the first encryption key KT;
• acquiring, by the UIM, the second encryption key KUT and a shared session key KUS between the UIM and the service provider from an authentication message including a procedure for encrypting the second encryption key KUT and the shared session key KUS with a third encryption key KU between the UIM and the service provider, by using the third encryption key KU;
• and
• decrypting, by the UIM, an encrypted group key GK included in a registration response message by using the acquired shared session key KUS, and decrypting content encrypted with a traffic key TK by using the decrypted group key GK.