RIPE Supply of IPv4 Internet Addresses Set to Run Dry for UK and EU ISPs

The boss of UK business ISP Andrews & Arnold (AAISP), Adrian Kennard, has warned that RIPE NCC, which handles the distribution and registering of internet addresses for most of Europe, is “forecast to run out” of IPv4 addresses this very weekend. But what does that mean for ordinary folk like you or me?

Any device that connects to the internet (e.g. home broadband router) needs to be assigned an Internet Protocol (IP) address in order to function but existing IPv4 addresses, of which there are around 4.5 billion, have been running out since the Internet Assigned Numbers Authority (IANA) allocated its remaining address blocks to the worlds five Regional Internet Registry’s (RIR) in February 2011.

Shortly after that the Asia Pacific Network Information Centre (APNIC), which covers most of the Asia Pacific region, became the first RIR to run out and most people expect Europe’s equivalent (RIPE NCC) to follow before the end of this year.

Once that happens ISPs will only be able to add new customers if they have plenty of IPv4’s to spare, force IPv4 address sharing (best avoided for all sorts of security and performance reasons) or begin connecting users through the replacement IPv6 standard. The latter requires a costly network upgrade, which many ISPs have been slow to tackle.

Adrian Kennard said:

“Technically, running out means [RIPE] are on their last block and are effectively in lock down so not giving ISPs any more addresses. In practice, there is a policy allowing one final block per ISP, but this is only a thousand addresses, which you can imagine is not very useful for the likes of BT or Virgin Media [ISPr EDITOR: Both BT and Virgin are believed to have enough spare IPv4’s to last several years].

So when will ISPs run out? Well, tricky. The forecast window has been down to 3 months for a while, so, in theory, ISPs should not have more than 3 months of addresses left! In practice all ISPs have (or should have) plans for how they are managing their remaining IPv4 addresses. You can expect changes in policy to happen now.”

In practice end-users (consumers) probably won’t need to worry about this as any credible ISP will have planned well ahead and know how to adapt. Indeed most providers are expected to use a dual-stack setup for years to come, which allows both old IPv4 and new IPv6 addresses to work alongside each other (otherwise neither standard is directly compatible with the other).

ISPreview.co.uk ran a much more extensive article on this last month (UK ISPs Respond to Readiness Fears on World IPv6 Launch Day), which also revealed details about how the country’s ISPs are planning to tackle the problem.

So will RIPE run out this weekend? It’s certainly possible and the July-August 2012 timeframe for depletion has been predicted before but in practice it’s very hard to know. RIPE’s own IPv4 Exhaustion Graph suggests that we might still have a couple of months left but it will surely happen very soon.