METHOD FOR AUTHORISING
A method for authorising access to multimedia digital programmes with access control and broadcast by a broadcast server ( 11 ) to descrambling devices ( 13 ) through a communications network, in which access request messages are transmitted for a reduced period of time, to a scrambled multimedia digital programme from descramblers ( 13 ) to a licence server ( 12 ); comparison in the licence server ( 12 ) of the request messages received with a specific trust level associated with a predetermined credit level stored in the licence server ( 12 ) and in which each customer is assigned a credit level; if the comparison is positive, transmission of an access authorisation and descrambling key from the licence server ( 12 ) to the descrambler ( 13 ), and retransmission of the authorised request messages received to the broadcast server ( 11 ), when the multimedia digital programme is being played or has finished.
1 . A method for authorising for access to scrambled multimedia digital programmes with access control and broadcast one way by a broadcast server to a set of customer descrambling devices through a communications network; wherein the method comprises the stages of:
Transmission of an access request message to a broadcast scrambled multimedia digital programme, including a descrambling device identifier and an identifier of a specific multimedia digital programme from the descrambler to an access licence server.
Comparison in the licence server of the descrambler identifier and of the identifier of a specific multimedia digital programme with a specific trust level associated with a predetermined credit level stored in the licence server, if the comparison is positive.
Reduction in the value of the credit level stored of an amount depending on the type of multimedia digital programme,
Transmission of an access authorisation and descrambling key from the licence server to the descrambler,
Retransmission of the authorised request message received to the broadcast server, when the multimedia digital programme is being broadcast or has finished, in order to charge the subscriber and
Transmission from the broadcast server of a recharging message in order to re-establish the credit level stored in the licence server.
2 . A broadcast server connectable to a set of customer descrambling devices through a communications network in order to broadcast scrambled multimedia digital programmes with access control; in which the broadcast server is adapted to receive an access request for a broadcast scrambled multimedia digital programme, including a descrambling identification device and an identifier of a specific multimedia digital programme, from an access licence server, once the multimedia digital programme is being played or has finished.
3 . Server in accordance with claim 2 ; where the broadcast server is adapted to transmit a recharging message in order to re-establish a credit level stored in the licence server.
4 . Server in accordance with claim 2 ; where the broadcast server is adapted to make the billing charge in a customer account associated with the requesting customer.
5 . A licence server for access to scrambled multimedia digital programmes broadcast one-way by a broadcast server to a set of customer descrambling devices through a communications network; the licence server is adapted to receive an access request message to a scrambled broadcast multimedia digital programme, including a descrambling device identifier and an identifier for a specific multimedia digital programme from the customer's descrambler.
6 . Server in accordance with claim 5 ; in which the licence server is adapted for comparing the descrambling identifier and the identifier of the specific multimedia digital programme broadcast with a specific trust level associated with a predetermined stored credit level; if the comparison is positive it reduces the stored credit level by an amount depending on the type of multimedia digital programme and transmits an access authorisation and descrambling key to the decoder.
7 . Server in accordance with claim 6 ; in which the licence server is adapted to retransmit the authorised request message received to the broadcast server, when the multimedia digital programme is being played or has finished.
8 . Server in accordance with claim 6 ; in which the licence server is adapted to receive from the broadcast server a recharging message in order to re-establish the stored credit level.
9 . A computer programme can be loaded in an internal buffer of a computer with input and output units and a processing unit, where the computer programme comprises codes which, when executed by the computer, cause the computer to perform the steps of claim 1 .