IPv6 Transition Mechanisms

Overall rating: 4.81 Instructor: 4.80 Materials: 4.76 more …

In an ideal world, IPv6 would be widely deployed in parallel with IPv4 years before the IPocalypse hit us. In reality, half of the world ran out of free IPv4 addresses, around 3-6% of the end-users have IPv6 access, and numerous access networks still lack baseline IPv6 support, forcing us to deploy various transition mechanisms.

This webinar will help you understand the implications of IPv6 transition mechanisms and give you the insight you need to seamlessly deploy IPv6 in your network.


This webinar is part of IP version 6 roadmap and accessible with standard subscription

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This section describes the challenges encountered in the gradual transition from IPv4 to IPv6 Internet, major transition mechanism categories (tunneling versus translation, stateful versus stateless), and map individual transition mechanisms into one of these categories.

Rapid IPv6 deployment

One of the major roadblocks to rapid IPv6 deployment is the legacy infrastructure, particularly in the access networks. This section details the gradual evolution of IPv6-over-IPv4 tunneling, covering the following technologies:

  • 6in4: Point-to-point IPv6-over-IPv4 tunnels that are still used by major tunnel broker services (example: Hurricane Electric);
  • 6to4: An attempt at a global IPv6-over-IPv4 overlay network that failed due to unreliable relay routers;
  • 6rd: When faced with IPv6 deployment over an IPv4-only access network, 6rd is your best friend ... assuming you can give each customer a unique IPv4 address.

Residual IPv4 deployment

With RIPE and APNIC being in the last /8 address allocation policy, it's impossible to give each new customer a global IPv4 address; service providers have to conserve the public IPv4 addresses by centralized Network Address Translation (NAT) or by assigning a range of ports within an IPv4 address to each customer.

Two successful residual IPv4 deployment technologies are described in this section:

  • DS-Lite was the first attempt to give dual-stack connectivity to clients in environments lacking public IPv4 addresses. Unfortunately its IPv4 component relies on stateful carrier-grade NAT44.
  • MAP-T and MAP-E, technologies based on the A+P (address+port) approach, solve the same problem as DS-Lite in a stateless (and thus more scalable and robust) manner.

Accessing old content

Some of the content will never be available on IPv6, but fortunately we have several transition mechanisms that can be used to give IPv6-only clients access to IPv4-only content:

  • NAT64 and DNS64 give IPv6 clients access to IPv4-only content. Unfortunately they also break DNSSEC and don’t work for IPv4-only applications (example: Skype).
  • SLB64 is a load balancing technology that you can use to give IPv6 clients access to IPv4 content hosted in your data center.

Target Audience

If you’re planning to design, deploy or operate an IPv6 network, you simply have to attend this webinar, regardless of whether you’re working in an enterprise or service provider environment.

About the Author

Ivan PepelnjakIvan Pepelnjak (CCIE#1354 Emeritus) has been designing, deploying, operating and troubleshooting IP-based enterprise and service provider networks since 1990. He’s the author of EIGRP and MPLS books published by Cisco Press, numerous articles and highly praised webinars, including Building Large IPv6 Service Provider Networks, IPv6 Security and IPv6 Transition Mechanisms.

His blog, where you'll find numerous data center- and IPv6-related articles, is usually considered one of the best technology-focused internetworking blogs.

More about Ivan Pepelnjak

Happy Campers

About the webinar

Ivans webinars, particularly the IPv6 materials have been extremely valuable to us in creating an IPv6 transition plan for a medium enterprise network in North America. Looking forward to future webinars, specifically ones directed at enterprise networks. Thanks

Greg Bird
Very interesting webinar. Thanks Ivan !
Benoit Chemin
Another detail, pragmatic session! Good, actionable information about networking deployment techniques that is built from experience and a detailed understanding of the available options.
Eric Hanselman
I thought the level and amout of content was just the right amount to give me a great overview of all the IPv6 transition mechanisms. I feel I have a good understanding of each one and how/where to apply them, and which ones will work best for my organization.
Bryan Browe
Very good way to come up to speed quickly, while gaining valuable insight into most relevant aspects of a technology.
mark Kouyoumjian

About the instructor

Ivan apologizes for going over time, but it's exactly his attention to a detailed discussion and an imperative to answer each question completely that makes his sessions so valuable.
Eric Hanselman
In my view, the webinar went a bit too fast. But again, this may have been the result of arriving late.

In a classroom environment, or perhaps if I hadn't arrived late, I think I would have asked more "stupid", consistency-check type questions, essentially asking the instructor to repeat things, perhaps in a somewhat different contrast, or in comparison to other things that have been said.

I should note that I find this harder to do in a webinar, because you miss things in framing your question.

Instead, I'll probably stop and start and go back when reviewing the recording when I get time.
Ivan did a great job presenting the material in a clear and concise manner, and added real world experience that brought the material to life. Answered all 4 of my questions I asked during the webinar!
Bryan Browe

About the materials

Lots of great detail in the materials! I often to back to them as a comprehensive reference on the finer points of implementation details.
Eric Hanselman
5 stars. what else can i say?
mark Kouyoumjian


Great IPv6 Transition Mechanisms webinar by @ioshints! Recommended when (not if) you need to find out the various options.
Wow Outstanding Webinar. I am amazed to see that 65%+ of the guests have more than 10 years in networking .... 9% 1-3y (me)