Downloadable conditional access and method of using conditional access image

The present invention discloses a conditional access system and a conditional access method using the image. The reception according to one aspect of the invention limit the system, the service key distribution protocol used by the service key management server that receives the service key management client assigns a service key from; Download conditional access pictures by using the service key, when the download is completed, download of the service key management server through the service key management client requests an update of the service key to the client; And updated the service key according to the request stored by encrypting the received restriction image, prior to execution of the stored received limited image, by using the service key material obtained via the service key management client to recover the received limited image It characterized in that it includes an execution control.