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I’m a Believer; the World is Running out of IPv4 Addresses!

September 24, 2012 - 2 Comments

By Gina Nienaber, Marketing Manager, Service Provider (SP) Marketing Routing and Switching

Once again, just in case you missed it, the world is really running out of IPv4 Addresses. This time it is for real and if you are not a believer yet, you can investigate and find the second of the worlds five Regional Internet Registries (RIRs) is about to run out of IPv4 addresses. News of this historic event broke last week through an Internet Society guest blog post by Axel Pawlik, Managing Director of RIPE. The blog announced we clearly have turned another page in the IPv4 history books as the Réseaux IP Européens Network Coordination Centre (RIPE NCC) has begun allocating their last IPv4 /8 blocks.  If you are not familiar with RIPE NCC they are the independent, not-for-profit membership organization that supports the infrastructure of the Internet in Europe. The most prominent activity of the RIPE NCC is to act as the Regional Internet Registry (RIR) providing global Internet resources and related services (IPv4, IPv6 and AS Number resources) to members in the RIPE NCC service region.

What does this really mean?  How many addresses are left to allocate? If you’re interested let’s take a deeper look.  The last /8 contains around 4.6 million IPv4 addresses which will now be distributed as one-per-Local Internet Registry (LIR) in an allocation of a /22 of address space (1024 IPv4 addresses) to those who can justify the need for the addresses. Let’s peel the onion back a little further.  There are 16000 /22s left, of which one half can be distributed to new or existing LIRs. There are 8000 existing LIRs and assuming each existing LIR justifies the need to for a /22, that only leaves 8000 /22s for new LIRs. Keep in mind; most LIRs are Internet Service Providers, enterprises or academic institutions and 8000 /22s will not go a very long way when we are talking about allocating IP addresses to net new enterprises, ISPs or academic institutions. If you would like to learn more about IPv4 address allocation and assignment polices for RIPE NCC service region you can click on here.

All of this talk about IPv4 address exhaust, is exhausting, so let’s cut to the chase.  If you have anything to do with IP Address management and you live in Europe you should be boarding the IPv6 train, because it is definitely leaving the platform with or without you. If you don’t have IPv6 address space you can find the rules for RIPE NCC IPv6 address allocation and Assignment in Europe here.  If you are still not convinced and need further data points on IPv6 adoption rates around the world you can go to the Cisco’s IPv6 Deployment Statistics website and track IPv6 adoption on a per-country basis.  If you would like to see how far we have come since World IPv6 Launch in June you can read Alain Fiocco’s (Senior Director, IPv6 High Impact Program) blog on IPv6 adoption since the launch.

If you still don’t know what to do about IPv4 address exhaust and IPv6 implementation you can reach out to your Cisco account team who can engage Cisco’s IPv6 Advanced Services Experts. This team offers such services as IPv6 Discover Workshop, IPv6 Readiness Assessment, IPv6 Design, IPv6 Deployment and implementation services. To read further about Cisco IPv6 Advanced Services click here.

In closing, whatever you do, don’t get left standing on the platform at the station. The IPv6 train is leaving. Axel Pawlik, Managing Director of RIPE said it best  in his ISOC blog “It’s not enough to just have an IPv6 allocation; all stakeholders need to understand – and act upon – the now very urgent need to deploy IPv6 on their networks to ensure that the future Internet remains reachable for everyone.”

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  1. Very true and nicely done!

  2. …That’s for real…and always ready for any change, any time…Thanks for sharing, this note enhances our Cisco Networking academy class’s presentations…thanks again. Regards from Puerto Rico.