| 摘要 |
The invention relates to a method for validating access to a product (P1) by means of a security module (SM) associated with a user unit (STB) connected unidirectionally to an access control system transmitting management messages addressed to the security module (SM), said messages being generated by the access control system (CAS) following the reception of a request for a right of access to a product consisting of broadcast digital data. Said method comprises the following steps: a product (P1) proposed by the user unit is purchased and the security module (SM) checks that the amount associated with the product (P1) is covered by the remaining credit; in the event of a positive response, a code (CP1) representing the product (P1) purchased is determined; said code (CP1) is displayed on a visualisation element associated with the user unit (STB); a request (RQ) comprising at least said code (CP1) and an identifier (ID'SM) representing the identifier (IDSM) of the security module (SM) is transmitted to the administration centre (CG) via a channel which is independent of the user unit (STB); the validity of the code (CP1) and the identifier of the security module (IDSM) is checked by the access control system (CAS), and a rights confirmation message (CEMM) addressed to the user unit (STB) associated with the security module (SM) is transmitted. The invention is characterised in that during the purchase of the product (P1), a temporary right (D1t) is written into the security module (SM) when the remaining credit is equal to or higher than the amount associated with the product (P1), said temporary right (D1t) being replaced by a definitive right (D1) by the rights confirmation message (CEMM) received from the administration centre (CG), the definitive right (D1) authorising the access to the product (P1) purchased by debiting the amount associated with the product (P1). |
