Anyone implemented such a solution to priotirze youtube traffic ( I guess I have to use layer7) starting from the CPE till the core router ?
Good day to you my friend. This should work just as well as giving priority to web traffic - the same way. If you want the traffic to get more of all the internet you must do something in your main router/access concentrator. Is it RouterOS ?
P.S. proper caching is always a good idea, if you can afford the energy and time and hardware for it : http://cachevideos.com/