Bind
BIND (Berkley Internet Naming Daemon) can be used to run a caching DNS server or an authoritative name server, and provides features like load balancing, notify, dynamic update, split DNS, DNSSEC, IPv6, and more.
A DNS (Domain Name Service) is an Internet service that maps IP addresses and fully qualified domain names (FQDN) to one another. In this way, DNS alleviates the need to remember IP addresses. Computers that run DNS are called name servers.