Summary

Private addresses and NAT are a near-perfect pair of complementary technologies. Together, they have done wonders to stave off the Date of Doom and the collapse of the Internet's address space. I say near-perfect because there have been many unanticipated side effects. We examined some of the more prominent technical implications in this chapter. There has been political fallout, too. For example, it is now nearly impossible for a private enterprise to convince the various regional registries of the need for directly registered address space. Organizations that try are usually informed that their needs would be better met with RFC 1918 addresses and NAT. Part IV of this book looks a bit more closely at the implications of this policy shift.

In Chapter 8, "Internet Names," we'll look at a different aspect of IP addressing: how it relates to domain and host names.