Design of a network interface unit for a picture archiving and communication system network operating at 200-500 Mbps

A description is given of the design of a network interface unit (NIU) for a third-generation picture archiving and communication system (PACS) network called PACnet. PACnet is designed to operate at a data throughput rate of between 200 and 500 Mb/s. This PACS network is a dual fiber-optic ring which integrates voice, data, and image communications. The NIU allows uniform access to the network. At each node in the PACS network, an NIU implements the data-link-layer and the physical-layer protocols. The design is simulated using the hardware description language VHDL. Also, the high-speed digital technologies needed to realize the NIU are discussed