What is IPv6?

The Next Generation of Internet Addressing

IPv6 (Internet Protocol version 6) uses 128-bit addresses to provide a virtually unlimited number of unique addresses. CleanBrowsing supports IPv6 DNS resolvers alongside IPv4.

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Step 1: What is IPv6?

IPv6 is the most recent version of the Internet Protocol, designed to replace IPv4 as the world runs out of 32-bit addresses. IPv6 uses 128-bit addresses, written in hexadecimal groups separated by colons — for example, 2a0d:2a00:1::.

With 2^128 possible addresses (approximately 340 undecillion), IPv6 provides enough IP addresses for every device on earth — and then some. This eliminates the need for workarounds like NAT and CGNAT.

Step 2: IPv6 vs IPv4

  • Address size: IPv4 = 32 bits (4.3 billion addresses); IPv6 = 128 bits (340 undecillion addresses)
  • Format: IPv4 = dotted decimal (185.228.168.168); IPv6 = hexadecimal colon notation (2a0d:2a00:1::)
  • NAT: IPv4 relies heavily on NAT to share addresses; IPv6 gives every device a globally unique address
  • Auto-configuration: IPv6 supports SLAAC (Stateless Address Autoconfiguration), allowing devices to configure themselves without DHCP
  • Security: IPv6 was designed with IPsec support built in, though it's optional in practice

Both protocols coexist today through dual-stack networks, where devices have both an IPv4 and IPv6 address. DNS filtering works identically across both.

Step 3: IPv6 and DNS

IPv6 intersects with DNS in two ways:

  • AAAA records: While A records map domains to IPv4 addresses, AAAA records map domains to IPv6 addresses. On the authoritative side, NOC.org manages these DNS records for domain owners
  • IPv6 DNS resolvers: CleanBrowsing provides IPv6 resolver addresses so networks running IPv6 can use DNS filtering. See our filters page for the full list of IPv4 and IPv6 resolver addresses

CleanBrowsing's DNS filtering applies the same rules regardless of whether the query arrives over IPv4 or IPv6. Your filter profiles, blocklists, and allowlists work identically on both protocols.

Configure CleanBrowsing on IPv4 or IPv6

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