This paper describes basic fast-packet switching network attributes, providing background about the operation and advantages of fast-packet technologies. Fast packet networks achieve their high throughput by lowering the processing overhead required for transport and shifting this responsibility to the terminal equipment at either end of the network. At the same time, these networks achieve great efficiency by statistically multiplexing data from several users onto a single transport path. Frame and cell relay technologies are discussed, with a brief . overview of the relative merits of each. This paper primarily focuses on architectural issues unique to providing fast-packet transport over hybrid fiber/coax (HFC) networks. Various transport topographies and multiplexing methods over the HFC network are described and discussed. Particular attention · is given to the return path, which presents unique challenges for achieving high throughput efficiency just where spectrum is currently most limited. Congestion considerations and the effects of BER on system throughput are also discussed.