
8
8
IPv6 Addressing
One might suppose that the most obvious difference between IPv4 and
IPv6 is the address space: IPv4 addresses are only 32 bits long, and IPv6
addresses are 128 bits long. And there are more differences in the way IPv6
uses those addresses. However, in another sense, address length will be the
least obvious change because it will be invisible to most users. Applications
carried over IPv6 networks must rely completely on the Domain Name
System (DNS) to correctly link IP host names to IPv6 addresses and
networks. DNS and IPv6 will be discussed in detail in Chapter 18.
In this chapter, we begin with a discussion of the IPv6 addressing