DNSSEC is a security protocol that is used to protect the Domain Name System (DNS) from various types of attacks, such as DNS spoofing and cache poisoning. It uses digital signatures to verify the authenticity of DNS records, which helps to prevent attackers from intercepting or modifying DNS traffic. DNSSEC is not directly related to blockchain technology, but it can be used in conjunction with blockchain-based DNS systems to provide an additional layer of security and authenticity.