As Pchar described above, Iperf can be used to check the bandwidth available on an end-to-end path of the IPv6 Internet, as well as packet loss and latency. As the throughput that can be measured with Iperf is low compared to the link capacities of core networks, it is more likely that this tool better fits usage in end site networks that want to check the performance they can get on end-to-end paths.

The “-V” option can be used with Iperf to use the IPv6 protocol. This option has to be explicitly mentioned on the client and server side.

Server side:
                $ iperf -s -V

Client side:
               $ iperf -c <Server IPv6 Address> -V