Net shakeup looms as IPv4 resources start running low
There's a bit of unused space, just behind the sofa
Analysis A new study has called into question the previous received wisdom that IPv4 addresses are running out, forcing the long-heralded move to IPv6.
The migration to IPv6 is needed because it offers a massively increased address space as well as advantages in mobility and security. The use of technologies such as Network Address Translation, which means corporate PCs all sit behind a small range of IP addresses, has held back the long anticipated move towards IPv6 for years.
More recently, the greater use of internet-connected mobile devices has been eating up IPv4 address space. Or so many reckon.
However, a study by cloud security firm Zscaler published last week paints a very different picture. Zscaler reckons that despite reports stating we’re running out of IPv4 address space, much of the internet remains untouched.
Mike Geide, senior security researcher for Zscaler, explained: "Allocated, public IPv4 space by nature is used to provide internet accessible services and content. Web, mail, and DNS make up the majority of these Internet services."
The firm's findings were drawn from a study of sites visited by Zscaler customers, which it reckons provides good insight into the portions of the web that are being leveraged by enterprises.
"From Zscaler's large and diverse customer base and our billions of web transactions serviced, we are able to infer that the large amount of 'untouched' IP space from our customers is a good representation of internet as a whole," said Geide. "In other words, much of the IPv4 space is not utilised to provide public, internet-facing services or content."
Reports elsewhere, citing Internet Assigned Numbers Authority (IANA), which oversees the net address space, predicts that the entire pool of IPv4 addresses will be depleted by April 2012, the BBC reports. Major tranches will all go before then, or July 2011, according to the latest estimates.
Figures published in April from the The Number Resource Organization, which works with regional internet registries in allocating internet number resources (IPv6 and IPv4 addresses), estimate that just 7.8 percent of IPv4 addresses are left unallocated.
Pv6 was established as a replacement for IPv4, the current generation of Internet Protocol, by the IETF way back 1995. IPv4 has a 32-bit address space offering up to 4.3 billion addresses. IPv6 offers a much larger address space, due to the use of 128-bit addresses.
Support for the protocol has been available for years. For example, Cisco added IPv6 support to its routers and switches back in 2001. Mac OS X has supported IPv6 since 2006, with built-in support for Windows coming with the introduction of Windows Vista.
“The allocation rate of IPv4 addresses continues to increase due to the growing number of devices that require IP addresses - mobile phones, laptops, servers, routers, and more,” said Axel Pawlik, chair of the NRO. “We have also seen many new IP address requests from developing countries, whose populations are coming online more quickly than ever before.”
NRO reports that it made 186 IPv6 allocations in the first quarter of 2010, more than in the whole of any previous year, a sign that government, large organisations and service providers are beginning to switch over to the next generation internet protocol.
Black market fears
Mismatch between supply and demand in any market creates problems. The market for internet addresses is no exception to the hard rules of economics. Some recent reports suggest a black market in traditional IPv4 addresses is in the process of developing. This is of concern to many outside the sys admin community because it could have a knock-on effect on internet access prices.
Trial projects by the US government and others have laid the framework and helped to establish best practice for IPv6 migration but the process is far from straightforward and requires co-ordination. What's likely to happen is a co-existence of IPv4 and IPv6 addresses for the next five years or so.
After years of treating IPv6 migration as a low priority service providers and enterprises are beginning to talk seriously about roll-outs and deployments, if a recent post by network security firm Arbor are anything to go by. Even so many content providers, service providers and governments may still need a helpful push in the right direction before they are ready to make the plunge, Arbor's Carlos Morales explained.
"One challenge is that ARIN is still handing out IP address blocks with little to no resistance. This ensures business continuity but it also makes it so that some people, particularly those responsible for the bottom line, don’t perceive the gravity of the situation and hold back major IPv6 initiatives.
"The evidence of IPv4 exhaustion is so overwhelming that it is only a matter of time before the objections are overcome and major IPv6 initiatives begin across the Internet community." ®