IP traffic over ICMP tunneling
Not the first of its kind, just look-up in Wikipedia: <a href="https://en.wikipedia.org/wiki/ICMP_tunnel" rel="nofollow">https://en.wikipedia.org/wiki/ICMP_tunnel</a><p>Any captive portal these days block also ICMP.<p>Most firewalls block ICMP these days, because the days of blacklisting are over and ICMP is not the one who is getting white listed. Why?<p>The only way these days is to misuse DNS. But even that works less and less reliable.