The Domain Name System Security Extensions is a standardized protocol of communication allowing to resolve security problems related to DNS. We will begin by a reminder of what is the DNS.
How does the DNS work?
The DNS will allow web user to inform a domain name in his web browser to access a website. The browser will then “resolve” this domain name to obtain the IP address of the web server which hosts this website and displays it. We call this the “DNS resolution”.
To secure the integrity of the DNS resolution, DNSSEC develops a chain of trust that goes back to the DNS root (refer to the DNS root server image above). Data security is done by keys mechanism (KSK for Key Signing Key & ZSK for Zone Signing Key) which signs DNS records in its own zone. Public keys are sent to the corresponding register to be archived; the register being linked by DNSSEC to the root server, the chain of trust is developed. Each DNS parent zone ensures the keys authenticity of its child zones by signing them.