An industry first, this report, “A Decade of Passive DNS" provides an unprecedented snapshot of the use and popularity of top-level domains over a ten-year-period. The findings are based on what Farsight Security has seen in passive DNS from 2010-2019 based on a ten-year data rollup, excluding DNSSEC-related records. This "decadely" file allows us to report on four measures for that period for each of the 1,576 IANA-recognized TLDs:

  • The total number of unique RRsets (unique combinations of RRname, RRtype, Rdata, Bailiwick, sensor or zone data): 130,780,406,614
  • The total number of unique fully qualified domain names (FQDNs) seen: 51,326,781,632
  • The total number of unique effective 2nd-level domains (or "delegation points") seen: 1,071,823,976, and
  • The sum of counts, or total number of cache misses: 42,144,068,459,975.