Tue Apr 21, 2015 1:21 pm
Layer7 for YouTube and Facebook?!? Does that actually work? I'm guessing no one has yet tried to manually type "https" in the address bar (i.e. you have no users THAT knowledgeable)?
On that note, I believe the YouTube app uses HTTPS from the start (without making the user type anything), which is why you're not blocking it.
You can drop DNS packets to youtube.com/facebook.com, and also redirect all DNS requests to your router's DNS (to make sure users don't easily bypass it). Initially, users will still have access due to their device's DNS cache, but soon it will expire, and they won't.
In theory, users could bypass this restriction, even on an Android phone, by modifying their hosts file, but in practice, most users don't know how to do that, so you're safe.