Combination local ATM segmentation and reassembly and physical layer device

An ATM network interface comprising a physical layer interface having transmit and receive line interfaces, transmit and receive framers and overhead processors coupled to respective ones of the transmit and receive line interfaces and transmit and receive cell processors coupled to respective ones of transmit and receive framers and overhead processors. The interface further includes a segmentation and reassembly interface coupled to the physical layer interface having transmit and receive ATM and adaptation layer processors coupled to respective ones of the transmit and receive ATM cell processors and a transmit ATM Traffic Shaper coupled to said Transmit ATM and Adaptation Layer Processor, and a coupler to couple the segmentation and reassembly interface to a PCI bus. By incorporating the SAR unit on the same monolithic device as the remainder of the interface, one is able to eliminate the need for expensive external static RAM or SRAM for connection context memory.