The French 3-strikes law does not mandate anything like that. It only says that you should make sure your access is not used for downloading illegaly, but does not specify how. (And no decree was published, afaik).
Ah, yeah, true. And fortunately, they are not that dumb as to hurry up and make things worse than they already are... or are they?
Orange (major French ISP) tried to monetize a securization solution based on a 2€/month contract that would block P2P traffic from unauthorized WLAN clients directly on the box. The solution was hacked within days (hours? not sure), simply by grabbing plain-text IP adresses of all the users with a simple /status http query to the webserver of the service provider, and injecting them on random P2P networks using IPFuck (sic), de facto forcing all customers to break the law.
Orange retired their solution from the market and decided to never again try to take on that subject.
Right now the only official stance from HADOPI (3-strikes organization) is a recommandation to use WPA2 instead of WEP. Still no means of securization, so if you get caught, you're to blame for not doing something nobody knows how to do.
