As we have reported several times, after massive upgrades of the anycast DNS for the .CZ domain zone in recent years and building of the 100GbE DNS infrastructure, we are now focusing more on targeted tuning of the anycast operation. For example, we try launching new DNS stacks in the locations of significant DNS traffic sources, both abroad and in Czechia. The launch of the DNS stack on the CESNET network at the beginning of April is the most recent fruit of this work.
On the 15th of November, following the prior maintenance notification, our system administrators have successfully installed a new version of FRED, the system that is the basis of the .cz domain name registry (as well as national domain name registries in a dozen of other countries). What does that actually mean though?
For many years, our association has been running a service going by the acronym “ODVR” – Open DNSSEC Validating Resolvers. At times when DNSSEC was just beginning, we thought it was necessary to come up with an alternative to DNS resolvers provided by ISPs who introduced the validation support too slowly. Since then, we have offered a publicly available service that allows validation of domains using DNSSEC security even in those networks whose default DNS resolvers do not support this.
DNS records contain a lot of important data, including the information on how quickly such data becomes obsolete, the so-called TTL (Time To Live). TTL in the DNS indicates for how long the data can be stored on a recursive nameserver (resolver) without it being retrieved from an authoritative nameserver. The lower the TTL, the more frequently resolvers query authoritative nameservers and obtain the most recent data. At the same time, however, a short TTL causes heavier load on nameservers, and if DNS records do not change often, the TTL is usually set to several hours.
This year’s December 5 made it into the history of Czech Internet security by crossing a significant threshold. From this date, in the registry of .cz domains there are more domains with DNSSEC security than those which lack this protocol extension. Information provided by DNS systems of more than 51% (653,297) of .cz domains can now be authenticated to ensure that it was not spoofed on the way to the user.