What is a Nameserver?

Authoritative vs Recursive DNS Servers

A nameserver is a DNS server that responds to queries about domain names. There are two main types: authoritative nameservers (which store DNS records) and recursive resolvers (which look up records on your behalf). CleanBrowsing operates as a recursive resolver with built-in filtering.

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Step 1: What is a Nameserver?

A nameserver is any server that participates in the Domain Name System by answering DNS queries. When you type a URL into your browser, nameservers work together to translate that domain name into an IP address.

The DNS system has a hierarchical structure: root nameservers at the top, TLD nameservers in the middle, and authoritative nameservers for individual domains at the bottom. Recursive resolvers navigate this hierarchy on behalf of users.

Step 2: Authoritative Nameservers

Authoritative nameservers are the source of truth for a domain's DNS records:

  • Store DNS records: A records, AAAA records, MX records, TXT records, CNAME records, and more
  • Answer definitively: When asked about a domain they host, they provide the authoritative answer — not a cached copy
  • Managed by domain owners: Domain owners configure their DNS records through their authoritative DNS provider
  • DNSSEC signing: Authoritative nameservers sign records with cryptographic keys to prove authenticity

NOC.org provides authoritative DNS hosting — managing the DNS zones where domain owners publish their records. This is the "phone book" that tells the internet where each domain lives.

Step 3: Recursive Resolvers

Recursive resolvers are the nameservers that devices actually talk to:

  • Accept queries: Your device sends DNS queries to a recursive resolver (configured in your network settings or router)
  • Chase referrals: The resolver queries root, TLD, and authoritative nameservers in sequence to find the answer
  • Cache results: Answers are cached according to their TTL to speed up future lookups
  • Apply filtering: CleanBrowsing's recursive resolvers add a filtering layer — checking queries against blocklists before returning results

CleanBrowsing is a recursive resolver that adds DNS filtering to the resolution process. Your devices point to CleanBrowsing's resolver IPs, and filtering happens transparently during every lookup.

Step 4: How They Work Together

The full DNS resolution chain works like this:

  • Your device sends a query to CleanBrowsing's recursive resolver
  • CleanBrowsing checks if the domain is blocked — if so, returns a block response
  • If allowed, CleanBrowsing queries the DNS hierarchy (root → TLD → authoritative nameserver)
  • The authoritative nameserver (e.g., hosted at NOC.org) returns the definitive answer
  • CleanBrowsing caches the result and returns it to your device

This separation of concerns means domain owners manage their records at the authoritative level, while network administrators manage access controls at the resolver level.

Use CleanBrowsing as your DNS resolver

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