A digital television receiving system having a security mechanism which simultaneously handles two or more separate television program signals is described. The system includes a plurality of digital television receiver mechanisms for receiving a plurality of separate digital television program signal transport streams. The system also includes a multiplexer mechanism coupled to the digital television receiver mechanisms for tagging and multiplexing the received program signal transport streams into a single combined signal transport stream. The combined transport stream is supplied to a security mechanism which limits usable access to the combined stream to authorized users. The system further includes a demultiplexer mechanism for receiving an access-allowed combined transport stream from the security mechanism and demultiplexing the combined transport stream into separate transport streams corresponding to the separate transport streams received by the receiver mechanisms. The system also includes circuitry responsive to at least one of the demultiplexed transport streams for supplying image signals to a television display mechanism for producing television images.