A long time ago (2011) when I was teaching the networking course at Brown, the final assignment in the course was to create the equivalent of iodine, IP-over-DNS tunneling [1]. Being a course assignment, the handout only outlines the solution. We provided a set of domain names and DNS servers on VMs for students to use.
After the course ended, one student going home did manage to use his assignment to get Internet access from the airport, as we had forgotten to turn off the DNS server nodes.
Over the years we had a lot of fun with creative final projects in the course besides IP-over-DNS, including web-based phone tethering, DNS spoofing, openflow-based SDN routing, LT (Erasure) Coding, a BitTorrent client, and a DNS-redirection-based CDN with leaderboard.
After the course ended, one student going home did manage to use his assignment to get Internet access from the airport, as we had forgotten to turn off the DNS server nodes.
Over the years we had a lot of fun with creative final projects in the course besides IP-over-DNS, including web-based phone tethering, DNS spoofing, openflow-based SDN routing, LT (Erasure) Coding, a BitTorrent client, and a DNS-redirection-based CDN with leaderboard.
[1] https://cs.brown.edu/courses/cs168/s11/handouts/dtun.pdf