The speed of optical transmission links is growing at a rate which is difficult for the micro-electronic 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 Linköping 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. In this paper, 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.