Some of the root server operators post public statistics for their domain name traffic at the top-level. For example, the graph (which can take a bit of time to generate, given ICANN's slow servers) for the L-root server's most popular Top-Level Domain (TLD) queries demonstrates, to no one's surprise, that .com is king. What's more interesting, though, especially given the new generic Top-Level Domain (gTLD) debate, is to look at the most popular invalid (non-existent) TLDs. This list will vary depending on caching and the geographical location of the root server, but for the L-root, .local, .belkin, .home, .lan, .invalid .domain, .localdomain, .wpad, .corp, .maps, .html, .router, .host, .mshome, .htm and so on show popularity in the past week.

Given what transpired with the wildcarding of .cm, and the current lack of a prohibition of wildcarding for new gTLDs (despite our own input into the public comment periods), it's clear that these TLDs will be in demand by those who hope to take advantage of the built-in DNS traffic hardcoded into routers, LANs and other private networks, and from typos of existing TLDs.

I recommend that the Security and Stability Advisory Committee compile statistics on invalid TLD queries across all root servers, and from popular ISP-run DNS servers, in order to create a Reserve List. The list of at least the top 1000 invalid TLDs should be made public to ensure transparency, and be pruned only with the consensus support of the community.