A system for deriving multiple channels from four-wire residential telephone wiring. The invention provides two voice channels and two, or more, data channels on common residential telephone wiring. The voice channels occupy a normal telephone bandwidth, in the range of approximately zero Hz to 3500 Hz. With this channel placement, ordinary telephonic devices can use the channels, without a requirement of frequency-shifting. Above these voice-channel frequencies, data channels are provided, for internal communication within the residence.