Many ISPs do not shape traffic on their provided Internet connections, which can cause “bufferbloat,” i.e. high latency induced during high upload or download activity. You may see high ping times when you are uploading photos/videos or performing an online backup.

To fix this, configure your WAN connection to use CAKE (Settings->Networks->WAN->WAN1, etc.). Under Advanced, set the Download and Upload limits to match your contracted ISP upload/download speeds. In some cases you may need to subtract 5-15% of your contracted rate, to account for your specific connection’s overhead. Then hit Save.

This will enable CAKE, which uses heuristics on the packets traversing through your Internet connection to prioritize smaller, more important ones above bulk ones. This is also called “Traffic Shaping,” i.e. the Route10 will attempt to fit a specified amount of traffic into and out of your Internet connection, to ensure there is enough overhead for high priority packets.

For more advanced QoS, please see this article.