Recursive Resolver

A Recursive Resolver is a core component of the Domain Name System that performs DNS name resolution on behalf of clients. When the server receives a request for the IP address associated with a domain, it retrieves the required information from the DNS hierarchy if the result is not already available in its cache. It typically queries the relevant DNS servers step by step, including root name servers, Top-Level Domain name servers and ultimately the authoritative name server for the requested domain. The result is returned to the client and usually cached for a period determined by the Time to Live value. Caching enables repeated DNS queries to be answered more quickly and reduces the number of external requests. Recursive Resolvers are operated by Internet Service Providers, organisations and public DNS services.