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Ofcom mulls selling UK govt's IPv4 cache amid IPv6 rollout flak

Strategy picked apart by own expert

Comment The UK is in danger of falling behind the rest of the world in rolling out IPv6 networking, while Ofcom sees pound signs and focuses on workarounds, it's claimed.

In a thought-provoking blog post, internet policy expert Emily Taylor digs into the UK's adoption of IPv6 – an upgrade to internet infrastructure that experts have been pushing for more than a decade.

As the pool of available IPv4 addresses runs dry, the shift to IPv6 seems obvious, given the tech world is bracing for a possible explosion in internet-connected things, each potentially using IPv6.

Taylor was a member of the team commissioned by UK comms regulator Ofcom to review how IPv6 was being deployed in Blighty as well as a second report on the steps taken towards upgrading.

The reports made two findings. First, that the UK appears to be dragging its feet over implementing IPv6 connectivity, and second that carriers' stop-gap solution gluing today's IPv4 and future IPv6 networks together is not scalable in the longterm.

Taylor argues, with quotes from other experts and studies, that the likely reason the UK is falling behind is due to a lackluster effort by the British government and its watchdogs to push the transition.

Due to the cost of upgrading systems, and the fact there is little consumer demand, ISPs have been slow to roll out IPv6 to subscribers – so governments around the world are taking an active role in pushing it.

For example, the US has written an IPv6 requirement into all new government contracts, and the Swedish administration has taken the soft yet effective approach of repeatedly asking its internet service providers how their IPv6 deployments are going.

Short-term fix

Ofcom, however, has gone the other direction, Taylor claims, and despite the reports' conclusions, the regulator is apparently following the industry line that Carrier Grade Network Address Translation (CGN or CGNAT) is just fine for the future, and that there is a "lack of urgency" in getting IPv6 up and running natively everywhere.

That's something the world's internet experts fervently disagree with. And something that mobile operators – who have been using CGNAT for many years – say is a bad idea. In order to make IPv4 workarounds function seamlessly, it requires a huge amount of additional networking effort. One expert refers to it as a "necessary evil" while IPv6 networks are built. There are also a number of applications, including gaming, that won't always work with CGNAT.

Taylor notes: "Ofcom’s Infrastructure Report does acknowledge that CGN can be problematic, but it seriously downplays the issue. It advocates a mix of recycled IPv4 addresses and CGN as an alternative to implementing IPv6."

Follow the money

So why is Ofcom talking about recycling IPv4 addresses? One reason is giant dollar signs, or pounds, depending on which side of the Atlantic you're standing.

According to Taylor, "it seems officials have become excited at the idea of selling unused IPv4 address space." Ofcom notes in one of its reports that due to their scarcity and usefulness, IPv4 addresses are now selling for about $10 each.

“There may be ways to bring these unused blocks of addresses into efficient use," Ofcom ponders out loud [PDF, page 169], "for example, by recycling them to other UK based access and service providers." By "recycling," read "sell."

How many IPv4 addresses does the UK government own? According to IANA, it has two blocks of /8 addresses, so about 30 million – half allocated to the Department of Work and Pensions, and half to the Ministry of Defence.

A lot of those are in use, but Whitehall has come under pressure to sell off its unused addresses, as a full /8 block of IPv4 space is said to be worth between $500m and $1.5bn (up to £1bn).

Of course, flooding the world with IPv4 addresses for sale will cause the unit price to drop; the return will never be as high as nine-figures, in reality.

And efforts to establish IPv4 address block markets have been going on for a number of years, and have even been studied by the OECD. In each case though, apart from a few high-figure one-off purchases, the general feeling has always been that the solution is to simply move over to an IPv6 infrastructure.

Ofcom, it appears, hasn't got the memo, and "seems to be suffering from organisational paralysis on IPv6 implementation," says Taylor. She concludes: "The idea of the UK regulator advocating recycling of IPv4 addresses to help ISPs avoid the expense of implementing IPv6 seems perverse."

A spokesman for Ofcom told The Register on Monday: “Ofcom believes that the transition to IPv6 can help address the limits of the IPv4 address space, and we welcome major UK ISPs’ intention to introduce IPv6 in 2015.

“But it is widely acknowledged that IPv4 and IPv6 will need to run in parallel for some time after the introduction of IPv6, and UK service providers will therefore need to work with the constrained IPv4 space for a while.

“We believe that making more effective use of the 40 million IPv4 addresses which do not currently appear on the internet, but have been allocated to UK institutions, is only one means of helping address this challenge.” ®

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