Pro DNS and BIND 10

Chapter 5. DNS and IPv6

While IPv6 provides many improvements in network management, one of the major driving forces behind its design was to greatly increase address space. An IPv4 address uses 32 bits whereas an IPv6 address uses 128 bits. Thus, IPv6 is theoretically capable of providing many millions of IP addresses for every human on the planet!

The original IETF specifications for IPv6 date from 1995 but the Classless Inter-Domain Routing and Network Address Translation (see the "IPv4 Addresses and CIDR" sidebar in Chapter 3) initiatives of the mid-90s effectively postponed the urgent need for additional address space. IPv6 usage until 2006 was largely confined to experimental networks such as the IETF's 6bone (www.6bone.net) and large-scale ...