Network Web Diagnostics
Network Path and Application Diagnosis - A more complex tool that requires knowledge of your round-trip time and target data rate. The results are more extensive than the NDT test and include host TCP configuration issues and suggestions for what the maximum rate can be.
Network Diagnstic Tester - This is a simple test and it will tell you the slowest link in the path between sites. It can also detect some errors such as duplex mismatches, high packet loss, and congestion
This tool will display the reverse network path from NAS to your system. Compare it to a traceroute to a NAS system to determine if there is asymmetric routing, high latency, or loops in the path..