This article gives enterprises an IPv6 reality check by discussing the IANA's recent Internet Protocol version 4 (IPv4) depletion and what it really means for
The long awaited demise of the IPv4 address space is finally upon us as the Internet Assigned Numbers Authority (IANA) recently allocated its last remaining blocks of IPv4 address space out to regional registries for distribution. But is it Y2K all over again? Is now the time to drop everything and spend whatever it takes to convert IPv4 networks over to IPv6 as soon as possible or face exile from the Internet? Not exactly.
Let’s step back and take a deep breath. Yes, it’s true that the available IANA address blocks are gone. But an IPv4 depletion from the IANA doesn’t mean we’re out of available IPv4 address space just yet. Regional Internet Registries (RIRs), like RIPE, ARIN, APNIC, etc., still have address space left to allocate. As Global Crossing’s Dave Weigel and APNIC’s Geoff Huston have noted, registries won’t begin to run out of space until late 2011 and early 2012. Beyond that, most ISPs still have enough space to support their customers’ needs for the short term -- either via direct allocations of existing reserves, via NAT or through further subnetting of available space.
And there are other possibilities to extend the IPv4 lifespan. Registries and ISPs can attempt to reclaim excess IPv4 address space from organizations that in the early days of the Internet received far more address space than they ever needed. We could also see service providers or numbering authorities create an IPv4 market that enables those with excess space to sell it to those who need it.
So IPv4 depletion from the IANA is no problem, right? Again, not exactly. We can’t ignore IPv6 for the next few years, but service providers, content providers and end users still have time to craft a strategy for IPv6 migration. Less than 5% of IT leaders tell us their organization has an IPv6 implementation plan, and those that do are driven not by IPv4 depletion concerns, but by the need to meet government mandates to interoperate with IPv6 networks. This has to change.
So what should enterprise network architects concern themselves with now? Find out in the following tips in this series:
- Create an IPv6 migration strategy: The very least enterprises should do
- Five steps for overcoming IPv6 planning pitfalls
For further reading, view this Q&A with IPv6 expert Scott Hogg answering these questions: What will IPv4 address exhaustion mean for your network? Does your business network need an IPv6 transition? Who needs IPv6?
This was first published in February 2011