Will the world end? Will the Internet grind to a screeching halt? Will your computer systems disintegrate into a pile of bits and bytes? In short, no. At least not yet. But you may want to consider a few things.

ISPs aren't stupid enough to cut off IPv4 access as they begin rolling out . If they did, only a tiny fraction of websites on the Internet would be accessible at this time because most content providers haven't yet connected their Internet-accessible systems to the IPv6 Internet. The ISP's subscribers would revolt, flood the ISP with service calls, and take their business elsewhere.

But this presents an interesting dilemma for ISPs. If the reports of IPv4 shortages are true (and they are), how does a service provider continue to expand its subscriber base? This problem is most acute in Asia where the growing middle class is coming online and ISPs are starting to run out of IPv4 space. America and Europe aren't far behind.

ISPs in this situation are starting to deploy IPv4 and IPv6 in a dual-stack configuration for their customers. The IPv6 addresses are globally unique, but the IPv4 address is shared by multiple customers. This sharing of IPv4 addresses is a band-aid for IPv4 address depletion. How does it work? By adding another layer of Network Address Translation (NAT).