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Well, the short answer is because we need to communicate and our current system isn’t really cutting it anymore—kind of like how the Pony Express can’t compete with airmail. Just look at how much time and effort we’ve invested in coming up with slick new ways to conserve bandwidth and IP addresses. We’ve even come up with Variable Length Subnet Masks (VLSMs) in our struggle to overcome the worsening address drought.
It’s reality—the number of people and devices that connect to networks increases each and every day. That’s not a bad thing at all—we’re finding new and exciting ways to communicate to more people all the time, and that’s a good thing. In fact, it’s a basic human need. But the forecast isn’t exactly blue skies and sunshine because, as I alluded to in this chapter’s introduction, IPv4, upon which our ability to communicate is presently dependent, is going to run out of addresses for us to use. IPv4 has only about 4.3 billion addresses available, in theory, and we know that we don’t even get to use all of those. Sure, the use of Classless Inter-Domain Routing (CIDR) and Network Address Translation (NAT) has helped to extend the inevitable de....