The Internet Storm Center blog has a great writeup of q+a regarding hitting the limit of IPv4 address space.3 – A lot of IPv4 space is still unused. Why don’t we use it more effectively? The problem is not just that we are running out of addresses, even though that is the killer issue here. Assigning addresses more effectively would mean that assignments would become smaller and routing tables would become more complex. In order to make this work, we would have to essentially “renumber” the internet, and still be out of addresses at some point. 6 – So I can just wait and do nothing? No. What you should do tomorrow (maybe today?) is setup a test lab to familiarize yourself with IPv6. It is easy to get going. Ask your ISP if they support it (or when), or setup a tunnel with a free tunnel provider like Hurricane Electric  or Sixxs  (there are others). You need a plan on how to deal with it. Even if you don’t need IPv6, maybe your business partners start using it and you need to connect to them via IPv6.
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