We did some measurements on the round-trip (RT) values of DNS queries for SOA (Start of Authority) records from our RIPE Atlas probes, over both UDP and TCP. We plotted the TCP/UDP ratios on graphs, and found that, as expected, for the majority of the measurements, it is around 2. However, we also observed other values for some servers (including K-root). Upon investigation, we found that the K-root servers were configured to allow at most 10 concurrent TCP connections. This caused several much bigger RT values than on other root servers. When we changed the configuration to allow for 100 concurrent TCP connections, K-root showed ratios similar to the other root servers.
Pages created by Bert Wijnen
As part of our Data Repository, the RIPE NCC has released a new dataset. This dataset contains DNS lookups (A+AAAA), ping/ping6, traceroute/traceroute6 and HTTP fetches (IPv4/IPv6) from 53 vantage points (TTM, CAIDA Ark and others) to 60 websites involved in World IPv6 Launch. The data covers the period from 2012-05-19T00:00 to 2012-06-18T00:00 (UTC).