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Inside The Technology Used To Migrate To IPv6

Dyn’s Tom Daly previously gave a convincing argument as to what the migration to IPv6 means to the Internet, so now that you’re convinced that IPv6 needs to happen, what next?

Can’t we just flip a switch and have a new and improved Internet experience? If only it were that simple. The switch from IPv4 to IPv6 will take time and is no simple task.

As Dyn has a large contingent in Santa Clara, CA, this week for web speed and performance conference Velocity 2012, it seemed like a perfect time to discuss and review a number of technologies and concepts in play that can help us migrate from IPv4 to IPv6.


Imagine you’re traveling to an island for vacation and you need to take a ferry to get there.  While the Internet community transitions to IPv6, this same issue may arise where IPv6 is your car and IPv4 is the ferry. For this short segment, your packets will need to travel via IPv4 because IPv6 isn’t available.

The solution is called 6to4, where your IPv6 packets (like your car) are jammed into an IPv4 packet (the ferry) for shuttling to the next part of the trip. Then, just like your car, they are unloaded and sent on their way as the IPv6 message for delivery. This solution is only meant to be temporary since just like the ferry, packing one message into another simply isn’t efficient or beneficial if it can be avoided.


ipv6_ready_logoOne limitation of 6to4 is that it requires a dedicated IP address at the endpoint of the transition. This is often not available because people use network address translation (NAT), which disguises multiple devices behind one IP and the device itself doesn’t speak 6to4.

As a way around this, Teredo was developed to help manage traffic much the same way without being limited to networks without NAT. Many people have seen the name Teredo recently because it’s enabled by default in Windows 7. The important fact to note is that if an IPv4 address is available, the system will prefer that and not attempt to use Teredo.


Another dilemma about 6to4 is that it’s very dependent upon a number of key concepts to work correctly. Since the Internet is a collective group of different providers, relay points and subsequent routes aren’t always 100% correct and so sometimes the technology doesn’t work as expected.

A number of Internet Service Providers (ISPs) have opted to use a concept called 6rd, which runs entirely within the ISP’s own network. By running the system themselves, an ISP guarantees it will be setup the way they need to deliver as reliably as possible.

So when can you get IPv6 connectivity right to your home?  Many ISPs have tried pilot programs. IPv6 not available in your area yet?  Get ready by making sure your computer and browser are ready to visit an IPv6-enabled website.

Learn more about Dyn’s transition from IPv4 to IPv6.

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Oracle Dyn Global Business Unit, a pioneer in managed DNS and a leader in cloud-based infrastructure that connects users with digital content and experiences across a global internet.