13 ms·

Okay, how about this then. Here's some of the IP addresses of posts on the HN front page right now: 104.21.3.245 104.21.68.247 104.21.80.31 104.21.95.1

Okay, how about this then. Here's some of the IP addresses of posts on the HN front page right now: 104.21.3.245 104.21.68.247 104.21.80.31 104.21.95.131 104.21.112.1 104.26.4.133 None of them have reverse DNS records. Can you tell which is which?

AshamedCaptain 1y ago
So you take literally the worst possible set of IPs (all of them cloudflare), IPv4 only, and yet Copilot (!) is easily able to reverse 50% of them: 104.21.3.245 -- trebaol.com 104.21.80.31 -- diwank.space 104.26.4.133 -- daringfireball.net 104.21.112.1 -- simonwillison.net , taras.glek.net This was literally the worst example you could possibly do. I hope you kept which one was which, I'd like to know if Copilot was right. In the meanwhile, from the current top #30 articles on HN (also via copilot script, but I removed non-cloudflare IPs): ycombinator.com -- no CDN letsbend.de -- no CDN grepular.com -- no CDN xania.org -- cloudfront github.io -- no common CDN owlposting.com -- AWS, but IPv4 remained static netfort.gr.jp -- no CDN simonwillison.net -- cloudflare, 104.21.112.1 fixed folklore.org -- azure, 13.107.246.1-255 range danq.me -- no CDN nature.com -- fastly, IPv4 remained static daringfireball.net -- cloudflare, 104.26.4.133 ssp.sh -- no CDN trebaol.com -- cloudflare, 104.21.3.245 glek.net -- cloudflare, 104.21.112.1 gov.uk -- AWS, but IPV4 remained static phys.org -- no CDN diwank.space -- cloudflare, 104.21.80.31 free.fr -- no CDN (my French ISP, btw) ericgardner.info -- AWS, but IPv4 remained static ghuntley.com -- fastly, IPv4 remained static paavo.com -- no CDN railway.com -- cloudflare, 104.18.24.53 alloc.dev -- cloudflare , 188.114.96.2 Look at how many of them are self-hosted, have zero CDN, or otherwise return me always the same IP (even when I try from 3 different ISPs) which makes them trivial to reverse address. This is already a pretty huge success rate and all my context is that you browsed HN first (which I know, see first result on the list). Now imagine the tools a ISP will have at its disposal: - IPv6 - Its Geo region will actually match yours - Routing tables - The patience to also include resources fetched from these pages in the analysis (i.e. page X always gets its JS from Y domain which results in a constant Z KB transfer). - The rest of your browsing activity - The rest of everyone's browsing activity including most popular _current_ hosts for each hostname. Do you still claim that it is "impossible" to track your activity because of CDNs? I still bet you your ISP can do it with _100%_ accuracy.
- josephcsible 1y ago
  They're not all running single IP ECH yet. I was just making the point that it's not as trivial as a reverse DNS lookup, as you said it was.
  - AshamedCaptain 1y ago
    It took me the whole of one Copilot conversation to do the entire thing. Most of the top #30 results are in fact one reverse DNS away. The rest is not much more complicated. They're never going to be "1 IP ECH" . That would be the end of the Internet as we know it. If it ever happens that the majority of the WWW is 1 CDN, we have a bigger privacy problem than DNS. Much bigger.

AshamedCaptain 1y ago

So you take literally the worst possible set of IPs (all of them cloudflare), IPv4 only, and yet Copilot (!) is easily able to reverse 50% of them: 104.21.3.245 -- trebaol.com 104.21.80.31 -- diwank.space 104.26.4.133 -- daringfireball.net 104.21.112.1 -- simonwillison.net , taras.glek.net This was literally the worst example you could possibly do. I hope you kept which one was which, I'd like to know if Copilot was right. In the meanwhile, from the current top #30 articles on HN (also via copilot script, but I removed non-cloudflare IPs): ycombinator.com -- no CDN letsbend.de -- no CDN grepular.com -- no CDN xania.org -- cloudfront github.io -- no common CDN owlposting.com -- AWS, but IPv4 remained static netfort.gr.jp -- no CDN simonwillison.net -- cloudflare, 104.21.112.1 fixed folklore.org -- azure, 13.107.246.1-255 range danq.me -- no CDN nature.com -- fastly, IPv4 remained static daringfireball.net -- cloudflare, 104.26.4.133 ssp.sh -- no CDN trebaol.com -- cloudflare, 104.21.3.245 glek.net -- cloudflare, 104.21.112.1 gov.uk -- AWS, but IPV4 remained static phys.org -- no CDN diwank.space -- cloudflare, 104.21.80.31 free.fr -- no CDN (my French ISP, btw) ericgardner.info -- AWS, but IPv4 remained static ghuntley.com -- fastly, IPv4 remained static paavo.com -- no CDN railway.com -- cloudflare, 104.18.24.53 alloc.dev -- cloudflare , 188.114.96.2 Look at how many of them are self-hosted, have zero CDN, or otherwise return me always the same IP (even when I try from 3 different ISPs) which makes them trivial to reverse address. This is already a pretty huge success rate and all my context is that you browsed HN first (which I know, see first result on the list). Now imagine the tools a ISP will have at its disposal: - IPv6 - Its Geo region will actually match yours - Routing tables - The patience to also include resources fetched from these pages in the analysis (i.e. page X always gets its JS from Y domain which results in a constant Z KB transfer). - The rest of your browsing activity - The rest of everyone's browsing activity including most popular _current_ hosts for each hostname. Do you still claim that it is "impossible" to track your activity because of CDNs? I still bet you your ISP can do it with _100%_ accuracy.

josephcsible 1y ago
They're not all running single IP ECH yet. I was just making the point that it's not as trivial as a reverse DNS lookup, as you said it was.
- AshamedCaptain 1y ago
  It took me the whole of one Copilot conversation to do the entire thing. Most of the top #30 results are in fact one reverse DNS away. The rest is not much more complicated. They're never going to be "1 IP ECH" . That would be the end of the Internet as we know it. If it ever happens that the majority of the WWW is 1 CDN, we have a bigger privacy problem than DNS. Much bigger.