A high-speed communications network (10) provides singlecast, multicast, or broadcast image data capability and is implemented utilizing the High-Performance Parallel Interface (HPPI) as a physical channel. A server (12) includes both a HPPI receiver and transmitter. Workstations (18) support a HPPI-compatible receiver (14b), but require only a simplified HPPI output port (20). The workstations are connected such the receiver port of each is driven by data and control signals from an upstream server HPPI transmitter port. Handshaking signals, generated by the receiver ports, ripple upstream to the server or to an upstream workstation output port. A packet of data bursts corresponds to either a complete image frame, or to a rectangular subsection thereof, referred to as a window. A first burst is defined to be a Header burst and contains an Image Header that specifies addresses of addressed workstations. Following the Header burst are image data bursts containing pixel data organized in raster format.