30.06.2022 - 21:48 [ NIC.cz ]

Open DNSSEC Validating Resolvers

What is the CZ.NIC ODVR?

CZ.NIC ODVR are Open DNSSEC Validating Resolvers that you might freely use instead of the standard DNS resolvers offered by your Internet service provider.

What is DNS?

DNS (Domain Name System) acts like a phone directory for the internet IP addresses. It pairs the numeric IP addresses with labels, called domain names, that a user can easily remember and type in their web browser (e.g., if they look for a company called XYZ, they type in www.xyz.com). Just like a phone, the browser then searches the „directory“, looks up the right record, automatically connects to an IP address assigned to that domain name and finally displays the company’s webpage to the user.

More information is on the page About domains and DNS.

What is DNSSEC?

DNSSEC is an extension to the Domain Name System (DNS) that enhances its security. DNSSEC guarantees its users that the information they have received from DNS was provided by a right source, is complete and its integrity has not been tampered with. DNSSEC ensures the credibility of DNS information.

More information can be found on the page How DNSSEC works.

How to setup CZ.NIC resolvers?

Change your network configuration so that it uses resolvers with IP addresses and


You can verify the correctness of your setting via the test bellow.