Having download traffic within Web Surfing (or anything mis-categorized) shouldn't the end of the world. The guaranteed rates per category should keep everything functioning.
This means all categories UNDERNEATH web surfing will always get their guaranteed rate.
(The only issue with HTTPS downloads in "WebSurfing" would be that "WebSurfing" would use all the excess bandwidth available, and that excess would not be offered to the categories underneath it).
In your position, I would simply tweak the guaranteed bandwidths or lower the priority of websurfing if something not working to your liking and call it a day.
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Iptables is able to detect download traffic & override the traffic mark into what you desire.
The iptable rule would be
Code:-m mark --mark 0x80120000/0x80380000 -m connbytes --connbytes 1024000 --connbytes-dir both --connbytes-mode bytes -j MARK --set-mark ${Downloads_mark_down}
Currently, I see that connections are ONLY evaulated on initial opening. This was probably done for performance reasons.
If using the above rule, since the download would not initially be a considered a download and iptables would not be re-evaluating the connection at a later point in time, I don't think thenrule would take effect.
In past firmwares, I remember connections would be CONTIUALLY evaluated (maybe I had HW acceleartion disabled). In those firmwares, that rule should take effect and achieve what you wish.
You would have to research as to what firmwares that rule would still work on. Or potentially what parameter in the WebUI is preventing connections from being continually evaluated.
It really may be that HW acceleration only needs to be disabled for that rule to work. I haven’t messed around with that as I don’t want HW accel to be disabled. (It’s okay to do so on slow connections)
The problem is this also slows down normal web browsing tremendously as both downloads and regular web browsing get identified as "HTTPS over TLS SSL". I'm on a 5MBits connection. Probably, I don't have a lot of wiggle room.