When faced with a life changing situation such as the depletion of the IPv4 address space, the emotional reaction tends to track the Kübler-Ross model, better known as The Five Stages of Grief.
DENIAL: There is no crisis! There are lots of IPv4 addresses; we just need to reclaim the ones that are not used.
The increasing consumption rate of IP addresses combined with the natural inefficiencies inherent in IPv4 subnetting makes complete exhaustion of the IPv4 address space inevitable. In October 2010, a return of a “/8 block” (16 million addresses) added only one month to the depletion date. As of April 2011, the Asia-Pacific region alone consumes two /8 network blocks every month. No amount of conservation or reclamation can solve the problem.
ANGER: What a stupid design! How could we run out of addresses?
Vint Cerf sends his most sincere apologies. Nobody imagined the phenomenal growth of the Internet when Vint and his team defined the 32-bit IPv4 address space back in 1977. The good news is that the problem has been recognized since the 1980s and the IETF has had the successor IPv6 protocol defined since 1998. You can take advantage of more than a decade of experience in navigating this transition.
BARGAINING: I already have IPv4 addresses, and I’ve got NAT. Besides, I can buy more IPv4 addresses if I need them.
Even if you have IPv4 addresses, the devices to which you want to connect may not. Stateful translation devices can introduce potential points of failure, connection bottlenecks, and opportunities for suboptimal routing paths. While NAT has evolved into a very valuable, powerful and useful tool for coping with IPv4 address exhaustion, the very nature of NAT adds complexity to the network which can impede seamless end to end communication for things like gaming and IP location services.
The market for IPv4 addresses has not yet been established: Regional Internet Registries like ARIN still govern the transition of address space. Early pre-market transactions indicate that the address space will not be cheap.
DEPRESSION: I can’t cope with a change this big. I give up.
Arthur Schopenhauer famously said, “All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.”
It is not easy setting aside years of experience with an established protocol or facing change at such a large scale, but the growth trends of the Internet demand this change. Everyone will eventually need to take this path, and the process can be broken down into manageable phases. Together we will succeed.
ACCEPTANCE: I suppose I need to start looking at deploying IPv6.
Well done! Today is the day to begin that journey, and the Cisco IPv6 website is a great place to start. Cisco stands ready to help you through the suite of Cisco Professional Services for IPv6, and our World IPv6 Day – IPv6 Transition support community.