In a multimedia recording and playback network for receiving from a content server a service package of multimedia content, the network including a media server in communication with the content server, a method of securely transmitting a master encryption key from the content server to the media server, including the steps downloading a service package certificate from the content server to the media server, authenticating, in the media server, the received service package certificate, the content server providing to the media server a key server certificate, a public key of the content server, and a client certificate request, the media server authenticating the key server certificate, providing to the content server, upon authentication of the key server certificate by the media server, a client certificate including a challenge signature, and a public key of the media server, the content server authenticating the client certificate including the challenge signature received from the media server, the media server requesting the master encryption key from the content server, and the content server responding by transmitting the master encryption key to media server.