3 ms·

Can JavaScript measure DNS resolve time?

• cma 6y ago
  I think only indirectly, but if they control the endpoint they can ping you back, subtract rtt from initial request response time and then the difference from that can tell them whether initial request was cached in dns or not.
  • laumars 6y ago
    Just so I understand correctly, does that mean you then need to control the end point of every site you want to use as part of fingerprinting? If so, wouldn’t that drastically reduce the effectiveness of using DNS resolve times as a work around for Firefox containers? Not trying to be argumentative here, just trying to understand how effective the sandboxing is, or whether I need to design more layers of indirection. :)
• danielheath 6y ago
  It can measure response time. If you host your own dns and web server you can vary their response times and record from js.