A system for controlling a service access authorization with regard to an access-restricted service, comprising:na device for providing an authorization message for a user device with regard to an access-restricted service, comprising: an authorization message creator; and an identifier manager, wherein the authorization message creator is configured to generate an enabling message for enabling a service access authorization or an extending message for extending a service access authorization, the enabling message or the extending message being provided with a service-dependent user identifier provided by the identifier manager; wherein the identifier manager comprises a first block of associated service-dependent user identifiers in which an authorization time interval of a user device is running, a second block of unused service-dependent user identifiers in which the authorization time interval of the user device has expired by less than the predetermined duration, and a third block of service-dependent user identifiers released for being used again; and wherein the identifier manager is configured to leave a service-dependent user identifier unused for at least a predetermined duration after expiry of an authorization time interval of a user device to which the service-dependent user identifier was associated last, and to release the service-dependent user identifier for being used again by the authorization message creator after expiry of the predetermined duration;a first device for controlling a service access authorization for a user device with regard to an access-restricted service, comprising: a service access authorization provider, the service access authorization provider being configured to set a period of time in which the service access authorization is valid, responsive to an authorization message provided with a service-dependent user identifier, and the service access authorization provider being configured to disable an authorization allowing the service access authorization to be extended or reactivated using the previous service-dependent user identifier depending on whether at least a predetermined duration has passed since an end of a last authorization time interval for which a service access authorization was determined by the device, wherein the service access authorization provider is configured to determine the duration having passed and to compare same to the predetermined duration, and to disable the authorization for extending or reactivating using the previous service-dependent user identifier when the duration having passed is greater than or equal to the predetermined duration; anda second device for controlling a service access authorization for a user device with regard to an access-restricted service, comprising: a service access authorization provider, the service access authorization provider being configured to set a period of time in which the service access authorization is valid, responsive to an authorization message provided with a service-dependent user identifier, and the service access authorization provider being configured to disable an authorization allowing the service access authorization to be extended or reactivated using the previous service-dependent user identifier depending on whether at least a predetermined duration has passed since an end of a last authorization time interval for which a service access authorization was determined by the device, wherein the service access authorization provider is configured to determine the duration having passed and to compare same to the predetermined duration, and to disable the authorization for extending or reactivating using the previous service-dependent user identifier when the duration having passed is greater than or equal to the predetermined duration,wherein the system is configured to associate a predetermined service-dependent user identifier at first to the first device for controlling a service access authorization, and to associate the predetermined service-dependent user identifier, after being released for being used again, to the second device for controlling a service access authorization,and wherein the system is configured such that the authorization for extending or reactivating the service access authorization using a predetermined service-dependent user identifier is active in at most one of the first device for controlling a service access authorization and the second device for controlling a service access authorization, and wherein the first device for controlling a service access authorization and the second device for controlling a service access authorization are coupled to the device for providing an authorization message so as to receive the authorization message.
›11.↳ 10The system in accordance with claim 10, wherein the system is configured to transmit the authorization message via a digital video broadcast system or…d2
The system in accordance with claim 10, wherein the system is configured to transmit the authorization message via a digital video broadcast system or audio broadcast system, via a mobile radio system, via a line-switched or package-switched voice network or data network, an Internet protocol system, a GSM system or UMTS system or CDMA system, a GPS system or a DSL system in a conducted or wireless manner.
›12.↳ 10The system in accordance with claim 10, wherein the system is configured to use the same predetermined duration for the device for providing an author…d2
The system in accordance with claim 10, wherein the system is configured to use the same predetermined duration for the device for providing an authorization message, for the first device for controlling a service access authorization and for the second device for controlling a service access authorization, and wherein the system is configured to transmit the predetermined duration when enabling the service or to consider same to be a fixed quantity of the system or to determine same from known parameters of the system.
›13.↳ 10The system in accordance with claim 10, wherein the device for providing an authorization message is configured to provide a service-dependent user id…d2
The system in accordance with claim 10, wherein the device for providing an authorization message is configured to provide a service-dependent user identifier which comprises a range of values smaller than the product of a number of users registered in the system and a number of services registered in the system.
›14.↳ 10The system in accordance with claim 10, wherein the identifier manager of the device for providing an authorization message is configured to allocate …d2
The system in accordance with claim 10, wherein the identifier manager of the device for providing an authorization message is configured to allocate the service-dependent user identifier temporarily, and wherein the system is configured to block the service-dependent user identifier for the user of the user device to which the service-dependent user identifier was associated last after expiry of the service access authorization to the expiry of the predetermined duration.
›15.↳ 10The system in accordance with claim 10, wherein the system is configured to partly or completely encrypt the authorization message with a cryptographi…d2+1
The system in accordance with claim 10, wherein the system is configured to partly or completely encrypt the authorization message with a cryptographic key using an encryption algorithm and to transmit same in a partly or completely encrypted manner.
›16.↳ 15The system in accordance with claim 15, wherein the system is configured to transmit the authorization message in a partly or completely encrypted man…d3
The system in accordance with claim 15, wherein the system is configured to transmit the authorization message in a partly or completely encrypted manner using an encryption method.
›17.↳ 10The system in accordance with claim 10, wherein the system is configured to identify the authorization message using an electronic authentication meth…d2+1
The system in accordance with claim 10, wherein the system is configured to identify the authorization message using an electronic authentication method or an electronic signature.
›18.↳ 17The system in accordance with claim 17, wherein the system is configured to transmit the authorization message together with a message authentication …d3
The system in accordance with claim 17, wherein the system is configured to transmit the authorization message together with a message authentication code.
›19.↳ 10The system in accordance with claim 10, wherein the authorization message is specified in accordance with one of the OMA DRM, ETSI EUROCRYPT or ISMA s…d2
The system in accordance with claim 10, wherein the authorization message is specified in accordance with one of the OMA DRM, ETSI EUROCRYPT or ISMA standards.
›20.↳ 10The system in accordance with claim 10, wherein a user comprising an expired service access authorization is prevented from being able to access, by m…d2
The system in accordance with claim 10, wherein a user comprising an expired service access authorization is prevented from being able to access, by means of access data still present, the service access authorization of another user transmitted after expiry of the service access authorization using the same service-dependent user identifier.
