By default ksysguard is setup to with the following network sensors:

- network/interfaces/(?!lo|bridge|usbus|bond).*/receiver/data
- network/interfaces/(?!lo|bridge|usbus|bond).*/transmitter/data

When a VPN connection is active (as an example) when hovering over "Network History" graph the following interfaces are listed:

- eno1
- tun0

When looking at the traffic peeks they are exactly double of what one would expect based on numbers emitted by tools generating the traffic. Additionally, I created a graph of just tun0 traffic and it was exactly half the default graph.

This has been reported against ubuntu and gnome's system monitor: https://bugs.launchpad.net/ubuntu/+source/gnome-system-monitor/+bug/1076880. A possibly related bug: https://bugs.kde.org/show_bug.cgi?id=353497.

An example from my machine http://i.imgur.com/RkmrbIi.png.

Reproducible: Always

Steps to Reproduce:
1. Start VPN connection
2. Launch ksysguard
3. Perform VPN traffic with a known speed

Actual Results:  
Double the actual speed is displayed

Expected Results:  
The actual speed be displayed instead of summing virtual interfaces

It is rather misleading and should be fixed.