Buyer's Guide: Tips for small companies on IPv6 migration

There is no rush to switch from IPv4 to IPv6, but there is no harm in being prepared for IPv6. We look at the practical issues for SMEs.

By now, many people will be familiar with the fact that IPv4 internet addresses are set to run out and that there is a growing consensus that the problem should be solved by migrating to IPv6. There should also be some awareness of the other advantages touted with the newer protocol, including easier management, better end-to-end connectivity and improved security.

A quick web search will throw up numerous articles on the subject (another search will tell you the story behind IPv5). The Internet Society is another good source of information, and is also the organisation behind the next IPv6 Day on 6 June 2012, which is being promoted as a pivotal event in the slow switch from old to new.

This article looks at the practical issues for SMEs and provides advice on what should be done to prepare for IPv6 and what pressure there is to do so. 

On the face of it, things may not seem that urgent. There is nothing new about IPv6; it has been available since the late 1990s. It will still be easy enough to get new IPv4 addresses, especially with the use of network address translation (NAT), which allows many private IP addresses to hide behind a single public IP address for a router or firewall. For years, NAT has overcome the need for every single device to have a unique IP address.

Why switch

So why go through the pain of transition right now? Well, for starters the primary sources of IPv4 addresses are running out. Addresses are assigned in blocks via regional internet registries (RIRs), which in turn assign them to internet service providers (ISPs), businesses and other organisations. 

There are five global RIRs, the Asian one ran out of IPv4 addresses in 2011, the RIR for Europe (RIPE) is expected to do so in 2013. However, even this does not mean there are no more IPv4 addresses to assign, because large blocks of address space have been pre-allocated; but even they will run out eventually.

At present, many of the major internet content providers only respond via IPv6 to organisations that have been white-listed as IPv6-enabled. On IPv6 Day in 2011, participating content providers (which included Facebook, Google, Microsoft and Yahoo) white-listed all users for a day. It was deemed a success, so on the big day this year, the change will be made for good. 

After 6 June 2012, any organisation that is unable to handle IPv6 communications could be at a disadvantage, because they will have problems reaching pure IPv6 websites as they become more common. That said, any organisation that switches off IPv4 altogether would have worse problems in the short term, as many smaller content providers and most ISPs still do not fully support IPv6.

The primary sources of IPv4 addresses are running out

Support for IPv6

All the major IT hardware and software suppliers have been supplying equipment that is IPv6-ready for some time. For example, Microsoft has had support for IPv6 in Windows since the Vista release in 2007, and Cisco and D-Link are IPv6 Day participants, and from 6 June 2012 their equipment will enable IPv6 by default. 

That said, it is with user infrastructure that the problems start, because even if operating systems and browsers support IPv6, older routers and firewalls may not – and even if they do, some reconfiguration may be required. Certainly, when purchasing any new equipment and/or software, buyers should check that it supports IPv6.

Devices can be assigned both IPv4 and IPv6 addresses, allowing them to communicate via either protocol (called dual stacking), but doing this defeats the main objective of creating a huge number of new addresses. Sooner or later, parts of the internet and whole organisations must switch to pure IPv6. 

IPv6 devices can communicate with IPv4 ones using a technique call NAT-PT (network address translation – protocol translation), but then other benefits of IPv6 are lost. 

IPv6 “tunnels” can be created through IPv4 infrastructure, but firewalls may be configured to block them. This is deemed a sub-optimal approach by the internet society, because tunnels can “break” and lead to a poor user experience.

Application compatibility

Another issue is software applications. IPv6 requirements are often not considered, and it should be checked that your software developers and suppliers are adapting existing applications for IPv6, and support for IPv6 should be a criterion in the procurement or commissioning of any new applications. Another check any business should be making is that its own website can support IPv6, which may be down to the internet service provider (ISP).

Most SMEs link their infrastructure to the internet via ISPs, which are currently the weakest link. ISPs need to configure their own infrastructure and domain name servers (DNS) for IPv6. 

Most ISPs still fail the IPv6 test, which can be run from the IPv6 Day website; the advice given when this is the case is: “It looks like you have only IPv4 internet service at this time. Don't feel bad – most people are in this position right now. Most internet service providers are not quite yet ready to provide IPv6 internet to residential customers.” Many smaller businesses will be in the same boat.

Most ISPs still fail the IPv6 test, which can be run from the IPv6 Day website

ISPs signed up for IPv6 Day will enable IPv6 for “enough users so that at least 1% of their wireline residential subscribers who visit participating websites will do so using IPv6 by 6 June 2012”. They have also committed that IPv6 will be available automatically as the “normal course of business for a significant portion of their subscribers”. 

However, none of the UK’s major ISPs are listed by the Internet Society as signed up for IPv6 Day. Smaller ISPs, for example Claranet, say they can already pass the IPv6 test and have signed up. Content delivery network providers Akamai and Limelight are also participants, and will be enabling IPv6 throughout their infrastructure.

No rush to adopt IPv6

Those who bury their heads in the sand and continue to rely on IPv4 may not only face problems accessing content over time and a degraded user experience, they may pay a financial price too. As IPv4 address become increasingly difficult to obtain, a short-term premium priced market for them may develop – some worry there will even be a black market. However, such problems will drop off as IPv4 retreats to legacy islands over the next 10 years or so.

The much touted future of an “internet of things” can only become a reality in a pure IPv6 world

There is no need to panic. There is no do or die moment for any business in the transition to IPv6, and the rate at which it will be adopted is still uncertain and likely to be slow. The main goal of SMEs is to be prepared. IPv6 does need to be on the agenda in the procurement of all new hardware and software, and it is a discussion that must be had with ISPs – and if they do not at least have a roadmap, then consider changing to one that does. The much touted future of an “internet of things” can only become a reality in a pure IPv6 world.


Bob Tarzey is an analyst and director at Quocirca. His main area of coverage is route to market for ITC suppliers to enterprises, the mid-market, small businesses and the public sector.

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