[ars]

I think most VoIP providers let you block calls. Google voice does as well. As do most Cell providers, plus you can install apps on jailbroken cell phones that will do that.

It's really only POTS that doesn't have such functionality.

[CWuestefeld]

This is precisely why I moved to VoIP.

At least a couple of times a month for about a year, we'd get a fax call at around 2am. The phone company refused to do anything about it, saying that if it wasn't explicitly harassing, it was OK. That makes me not want to be their customer anymore.

So we switched to a VoIP service, which we can set up blacklists or whitelists for as we like. No more problems.

I think the underlying problem is that the TelCo just doesn't care: they're happy to lose you as a POTS customer. They lose money on residential service, so if they can go by the book for regulatory purposes and still shed those unprofitable customers, they're winning.

[guessbest]

This can be implemented on a PSTN, but I doubt any providers would bother to do it for a single, private customer. Shame really.