But that wouldn't come with baked in surveillance, so "what else can you do" sounds a bit unnerving.
It really wouldn't be.
Do that at OSI layer 3, every routed packet would have to have an "was this sent by a kid's device" flag.
Higher levels aren't the ISP's role. Lower levels, you'd need duplicate hardware specifically for kids, which couldn't connect to the adult's internet.
In the real world, we're still arguing about something that was already embarrassingly slow in its roll-out during my degree, and I graduated 20 years ago: IPv6.
This would also breed more interest in hardware modifications and thus leading more kids into the technical field. Sounds like a win win situation.
Such things can't run modern websites either.
We don't need to compromise here, this already exists and works pretty well.
Also, further up chain, I was replying to:
> if we're willing to shift these costs and responsibility to ISPs, which could separate the internet into two networks, one for children and the other for the rest of us. This is technically just as feasible, and probably cheaper than requiring every website to process
What you suggest is not that.
Also also, what you suggest puts the hard problem (configuring software correctly) in the hands of normal people.
Software configuration is second nature to us nerds, so it's easy to forget that the average person probably only knows how to install pi-hole and one or two VPNs: https://xkcd.com/2501/
I'm not making a comment with respect to the actual safety these systems offer, just that alternatives exist, which would not all require modified hardware.
> what you suggest puts the hard problem (configuring software correctly) in the hands of normal people.
Pre bundled software, specifically browsers, exist. Colleges use them all the time to prevent cheating, e.g. the Lockdown Browser. Those don't require the student to configure anything, they just download the application and login.