Given the availability of high-speed Ethernet and HW based protocol offload, clustered systems using a commodity network fabric (e.g., TCP/IP over Ethernet) are expected to become more attractive for a range of e-business and data center applications. In this paper, we describe a comprehensive simulation to study the performance of clustered database systems using such a fabric. The simulation model currently supports both TCP and SCTP as the transport protocol and models an Oracle 9i like clustered DBMS running a TPC-C like workload. The model can be used to study a wide variety of issues regarding the performance of clustered DBMS systems including the impact of enhancements to network layers (transport, IP, MAC), QoS mechanisms or latency improvements, and cluster-wide power control issues.