Following the recent articles on IPv6 that we have on the Intense School site, a couple of questions were asked regarding the adoption rate of IPv6 and also the recommended time to make the switch. This article aims to discuss these questions and possibly give answers to them.

What are the challenges involved in migrating to IPv6?

IPv4 has been around for a long time and will probably still be around for the next couple of years. Before we discuss the adoption rate of IPv6, we need to first consider some of the challenges involved in migrating from IPv4 to IPv6.

Lack of knowledge

I remember once downgrading a Cisco ASA image from version 8.3 to 8.2 just because Cisco had recently changed some configuration syntaxes which I was not familiar with. However, knowledge is the cure to ignorance. We usually fear what we don’t understand and it wasn’t until I went to study the new configuration syntax that I became comfortable with deploying the new Cisco ASA image version. In the same vein, I believe lack of knowledge in the field of IPv6 is one of the major challenges in the transition to IPv6.

Transition costs

Businesses have already made huge investments in IPv4 devices. Also, one of the main technologies that slowed down the exhaustion of IPv4 addresses is Network Address Translation (NAT). Considering that NAT works, even though it has its own problems, it may be difficult to justify the cost implications involved in transitioning to IPv6.

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For example, as an Internet user, you may not care how your traffic gets to the Internet, whether using IPv4 or IPv6, as long as it gets there. If ISPs don’t see the business case and there are no real policies driving the implementation of IPv6, then businesses may not be willing to make that investment.

Compatibility issues

IPv6 was not designed to be backward compatible with IPv4 and so companies must understand the issues that may arise with migrating to IPv6. These companies may still have legacy systems that do not support IPv6 and so they may be unwilling to adopt IPv6.

Is the IPv6 adoption rate really slow?

With the above challenges and a few others not mentioned here, the general perception is that the IPv6 adoption rate is slow. Furthermore, as a normal Internet user, the fact that I still use IPv4 to connect to networks makes me feel IPv6 is not catching on as fast as the proponents would have thought. But is that really the case? When the designers of IPv6 and other related parties thought about transitioning the Internet from IPv4 to IPv6, what was their forecast? How are we (you and I) measuring the adoption rate of IPv6? Is it just because we perceive that IPv6 is not widely implemented? Well, I will leave these questions open for you to think about and based on the information in this section, you can make your conclusion.

IPv6 has actually been around for a while now, over 15 years, but is just recently gaining momentum following the World IPv6 launch in June 2012. So how has IPv6 adoption really progressed over time? First, I will use data collected by Google amongst its users to discuss this progression.

As of the World IPv6 launch on June 06 2012, Google reported about 0.65% IPv6 adoption. One year later on June 06 2013, the rate had gone up to 1.29%, almost double the previous year. Again, one year after that on the 6th of June 2014, the rate had become 3.29%, which is more than 2.5 times the previous year. If the rate continues to increase at 2.5 times every year, then by 2017, IPv6 adoption rate would have passed the 50% mark.

Another chart provided by Akamai, a cloud services provider, shows an increasing number of IPv6 traffic over an almost 3 year period.

Finally, according to measurements on the World IPv6 Launch site, more networks are deploying IPv6 including Comcast, AT&T, Verizon Wireless and Time Warner Cable. You can view that data here.

From the above data and charts, we see that IPv6 is increasingly being adopted and even though IPv4 still accounts for more than 90% of the Internet traffic, statistics available to us show that IPv6 may catch up in the nearest future i.e. 3 to 5 years from now.

When is the best time to make the change to IPv6?

The next question then becomes when to move to IPv6. Theoretically, the answer to this question is “Now!” The fact that IANA has allocated the last IPv4 address block is a major reason to make the change. The continual rise in the use of mobile devices and the advent of the Internet of Things where more IP addresses will be required are also driving factors to make the switch to IPv6.

But with the challenges involved in migrating to IPv6, what is the reality? As a normal end user, until your ISP supports IPv6, you won’t be able to use IPv6. You can check if you are using IPv6 with this Google IPv6 test site.

Let’s assume your ISP supports IPv6; what of the websites will you be connecting to? Do they also support IPv6? There is a long list of websites that support IPv6 listed here. Also, you can check if a website site supports IPv6 through this link.

The use of private IPv4 addresses (RFC 1918 addresses) has helped enterprise networks on their internal networks (LAN). However, these networks also need to transition from IPv4 to IPv6 in order to enjoy all the benefits of IPv6.

In all cases, whether as a large ISP or a small network, it is important to develop a clear strategy for migrating from IPv4 to IPv6. A phased approach may be used where a section of the network will be migrated to IPv6 until the whole network is eventually migrated. Another option may be to use the dual-stack approach. Thankfully, many vendors manufacture dual-stack devices including Cisco and Microsoft.


Yes, there are challenges with migrating to IPv6 as with any other new technology; however, networks will need to transition to IPv6 at some point. We have seen above that more networks are already making the transition. Also, one of the cool things is that the transition from IPv4 to IPv6 was not meant to be an overnight job. That is why there are transition mechanisms like dual-stack, IPv6 tunneling and IPv6 translation.

IPv6 has not yet seen the widespread deployment that we think it should have but to answer the question of whether the adoption rate of IPv6 is slow or not, we need to first know what the transition plan was.

References and further reading

  1. World IPv6 Launch Measurements:
  2. Akamai IPv6 Traffic Volume: