Abstract: The present method and apparatus provide high-speed data multiplexing of telecommunications data signals. In one of many possible embodiments, an apparatus provides for high-speed multiplexing of Motion Picture Experts Group (MPEG) transport streams in a cable network. The apparatus includes an input interface, a demultiplexer, and an output interface. The input interface is configured to receive a number of transport streams carrying programming services. The demultiplexer is configured to access user-defined logic and to generate the internal transport streams based on the user-defined logic. The demultiplexer is further configured to add the programming services to at least one of the internal transport streams based on the user-defined logic. The output interface is configured to output the internal transport streams.