Dan Asimov <dasimov@earthlink.net> wrote:

I don't know about internet protocols and security, but:

How feasible would it be to ensure that every post or ad to any website anywhere (or at least in the U.S.) is correctly identified with its geographic location (to some reasonable precision)?

I'm no expert, but I can't see how it could ever be feasible. This email is a "post to a website" in the sense that all posts to this list are archived on a website (xmission.com). And I'm evading my location without even trying. First, KeithLynch.net is hosted in Minnesota, a state I've never even visited. Second, I'm not really posting from KeithLynch.net, I'm posting from Panix, which is in New York City. But I'm not actually in NYC. I've visted that city, most recently in 2004, but I've never lived or worked there. I'm actually in Virginia. A friend of mine who is more skilled at such things than I am was quite active on the net for several months in 2012, and the US government couldn't figure out his location, despite trying really hard. He was a federal fugitive at the time. They only caught him when he was injured in a bike crash and was hospitalized. In principle, though not in practice, the net could be completely rebuilt on different principles. But I doubt that would help. Even with the 19th century telegraph lines, it would have been trivial to link a telegraph sounder to a telegraph key, to relay messages from one line to another. Similarly with telephones. Similarly with letters -- just get someone to forward a letter to someone else. Public key cryptography can be used (until quantum computers break it) to prove who wrote a message. (Unless someone steals a private key, or beats it out of its owner.) But keys are associated with people or organizations. I can't see any way to associate one with a location, i.e. a key that anyone visiting my home town will somehow learn, but will forget the moment they leave.