A cost-efficient digital CATV network to improve
signal quality, provide reliability, and offer the ability to meet demands for interactive services is described. Analog or
digital video downstream channels are converted to a digital format by a digital headend
transmitter. Relatively costly error-encoding for
digital video channels is also part of the digital headend
transmitter. Downstream analog and
digital video channels in the digital format are transmitted using time-division
multiplex technology from a headend to nodes using standard network protocols, such as SONET. Standard network protocols provide error-monitoring and status indication of transmit data, thus ensuring high
signal quality and reliability. Time-division
multiplexing facilitates easy adding or dropping of information to a transmit path. Flexibility to add or drop information is critical in providing interactive services. Data from interactive services can be added or dropped at points of presence throughout the digital CATV network. Subscribers to the digital CATV network can communicate with each other. A digital node
transmitter receives the analog or digital video channels in digital format and converts the analog or digital video channels into an analog format. The digital node transmitter also frequency-division multiplexes multiple analog or digital video channels into one analog
broadband signal for broadcast to subscribers' homes.