Most censors employ the cheapest possible firewall solution for their blockades. And those, more often than not, involve merely blocking DNS requests. DoH (and

Most censors employ the cheapest possible firewall solution for their blockades. And those, more often than not, involve merely blocking DNS requests. DoH (and DoT to a lesser extent) mitigate censorship to an extent. Censoring HTTP/S connections by inspecting SNI (server name identification) field is prevalent, but it is defeated by clients like GreenTunnel and GetIntra.Org that split the SNI carrying packet in to two. A stateful (read: expensive) firewall can defeat this technique, but not many use it. And anyway, in this game of cat and mouse, Lantern and Psiphon, the two VPNs, have been faring admirably well.