The speed of optical transmission links is growing at a rate which is difficult for the microelectronic technology of ATM switches to follow. In order to cover the transmission rate gap between optical transmission links and ATM switches, ATM switches operating at multi Gbit/s rate have to be developed. A 10 Gbit/s/port shared memory ATM switch is under development at Linkoping Institute of Technology (LiTH) and Lund Institute of Technology (LTH) in Sweden. It has 8 inputs and 8 outputs. The switch will be implemented on a single chip in 0.8 μm BiCMOS. We report on a performance analysis of the switch under a specific traffic model. This traffic model emulates the LAN type of traffic. Performance analysis is crucial for evaluating and dimensioning the very high speed ATM switch