Here is a link to a decent CCNA packet tracer s imulationpackettracerlabs . html <| sep |> The moment you try to legislate what ISPs have to block on the internet , that means you need a way to enforce it , such that the ISPs can actually do it . It ' s not ISPs . The BBFC are in charge of the ratings , and really we might just be talking about Are you 18 ? tickbox . They don ' t know what technology will be used yet . But the important thing to note is that the BBFC are on public record as saying that they won ' t commit any enforcement and will notify ISPs about noncomplying websites . These laws are not targeted at people but at the websites . You should read this , it might provide a better understanding 11 th % 20 sits % 201 . 11 . 16 . pdfSkip to page 24 .