In most cases you can use utils like hping/iperf to test just the throughput potential of your network. This can bypass typical tcp/udp restrictions you’d face with real applications.
<a href=”http://dast.nlanr.net/Projects/Iperf/”>iperf </a> consists of a “server” daemon and a client. you can use that to see what the potential for transfer is betweeen two hosts.
Network performance testing can get complex. If you mean the application/protocol performance through some network. (eg. windows file copy – cifs/smb over an LAN ethernet), then you’;ll need to give us some more info. Like what is the physical/logical layout of your network. (ethernet/infiniband/wan/wireless/etc…)