Sometimes we need to check how fast our network connection is – with VPN without VPN. The most advanced tool is iperf – You can refer to it here (I used this tool to crash hyper-v cluster but usage is the same).
But sometimes we need simple graphic Windows tools. The one is coming with a very good 10 minutes config free VPN appliance like Softether. There is also a supported version from Marketplace.
But you can use traffic_test without installing Client or Server just download zip, unzip and press start.bat. You must Run Server on one and the client on the other end. The default connection metering protocol is TCP 9821 port. You can also test against the server provided by Softether.