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Now is the Time to Plan for Your IPv6 Transition

November 11, 2009 - 4 Comments

The Mayans had foresight that 2012 is going to be an epochal year. Now whether you agree the world is going to end or carry on is up to you. However what we do know is that the telecom skin encircling the planet, aka the Internet, will be suffering if we do not act now.

As the 4 billion IPv4 addresses run out sometime early next decade (current estimates: 2011-2012), the Internet will stop growing if we do not find ways to tackle the exhaust. The successor to IPv4 – IPv6 – allows 340 undecillion addresses or more than 50 billion billion billion per person on earth. Phew! However, the transition from IPv4 to IPv6 is not trivial and in a previous post I pointed out Large-Scale NAT (LSN) as one solution, which was also mentioned by Jeff Doyle of Network World. While LSN is a way to ‘preserve’ the life of IPv4 investments, new technologies are needed to ‘prepare’ for IPv4 and IPv6 co-existence. Both of these approaches will pan out over many years, and in the interim providers need to continue to ‘prosper’ from the boundless opportunities of the Internet.

This triad of preserve, prepare and prosper has been ably assembled in a blueprint by Cisco with the recent announcement of the Carrier-Grade IPv6 solution (CGv6) . The solution is powered by new product capabilities at industry-leading scale. For example, the Carrier-Grade Services Engine (CGSE) is a new module for the CRS-1 that supports LSN in the order of billions of translations and terabits of throughput. Additional CGv6 capabilities are being introduced in the ASR family and across the entire SP product set. Complementing the products, Cisco provides CGv6 Services to aid customers in making the transition in a controlled, safe and cost-effective manner.

Our customers around the world from Japan (NTT) to China (CERNET) to France (Free) agree on the need to undertake this transition soon.

My colleague, Doug Webster, had noted the industry’s concern on IP addressing during the ITU Conference earlier in September. I had similar discussions last month during SUPERCOMM. And recently the European Commission warned about slow preparations for IPv6. While none of us are predicting the end of the world, the industry certainly needs to plan for the day when the last IPv4 address will be handed out. And for sure I don’t think it will be anything close to what we are seeing in the movie trailers for 2012.

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  1. I’d certainly agree that there has been inaction on the part of enterprise and service providers and that both need to make preparations. The good news is that in recent dialog with Service Providers the urgency for IPv6 transition has picked up. They have also asked for tools to assist them during the transition – stateful and stateless IPv4/IPv6 translation, tunneling tools, and related technologies. For those service providers who cannot start on IPv6 immediately but need to manage IPv4 address exhaustion we can offer a large scale NAT (LSN) as part of our CGv6 solution. So we are supporting all of these options in product.Regulation could be helpful in some countries, but in many countries it is ineffective or impossible – the governing bodies don’t have the authority to make such a rule. We’re trying to educate people and provide solutions to ease migration.

  2. Couldn’t we make an internet regulation that all content providers hosting their sites on IPv4 must also do the same on Ipv6.. like having dualstack on their hosting servers..etc, Until 2011 I guess atleast we could have as many IPv4 websites hosted on IPv6 too.This would have the complexity of Translations reduced. Another point I would like to raise is enterprises are waiting for Service Providers to take the lead in transition and service providers are waiting for enterprise customers to avail Ipv6 services. I believe SP’s and Enterprises are thinking the Ipv6 ball is in the other guy’s court..

  3. Great comment and one that many raise. My take is that LSN (NAT44) is one of several forms of translation that help SP/enterprises address IPv4 run-out *and* transition to IPv6. We know how NAT44 works and that can immediately help with IPv4 run-out and buy time for IPv6 upgrades even after run-out in 2011. What you alluded to (using special IPv6 addresses with IPv4 inside) is exactly what v4/v6 translators use and that will enable IPv6 connectivity to IPv4 (and vice-versa). Same platform will do both and it will be up to the SP/enterprise to deploy as they see fit.

  4. I really do not understand why NAT or LSN”” still being clinged upon for this transition. NAT was a tempory fix which evolved to become a permanent solution “”But not Eternal””. The main issue in transition is the translation from V4 to V6 is in this current world of interoperability why is Ipv6 not backward compatible??? why can’t we look at other ways of inter-routing table or inter-forwarding table lookups?? .. Why can we make IPv4 address space compatible with IPv6 space like ::x.x.x.x?? If we are using LSN this will further make enterprises more reluctant to migrate to IPv6.”