I knew nothing about any of these subjects before doing this puzzle and I got it within 45 minutes, and the majority of that was digging through the ICMP RFCs t

I knew nothing about any of these subjects before doing this puzzle and I got it within 45 minutes, and the majority of that was digging through the ICMP RFCs to figure the first one out. It's definitely a test of if you can figure these things out unless you happen to know ICMP header codes, the weight of gold in an olympic-sized swimming pool, which company's data-link layer address starts with 08:00:09, and the html entity codes all off the top of your head.