The Chief Technology Officer (CTO) for business ISP Timico UK, Trefor Davies, has indicated that APNIC, which is one of five Regional Internet Registries (RIRs) charged with ensuring the fair distribution and responsible management of IP addresses, will ask the Internet Assigned Numbers Authority (IANA) for their two remaining normal /8 blocks of IPv4 addresses this week. This will mark the end of new IPv4 address availability.

An IPv4 address is assigned to your computer each time you go online (e.g. 85.23.56.198). These are a bit like the online equivalent of your home phone number, except now only a few million out of roughly 4.5 Billion addresses remain.

At present just two /8 blocks of IPv4 remain to be distributed along the normal method. Global policy says that once the IANA free pool is reduced to five /8 blocks (as will happen if APNIC's request is granted), they will all be simultaneously distributed to the five RIRS.


We read some reports last week that suggested APNIC would make the request within the "next few weeks" and indeed some had initially pegged February 2011 for the exhaustion of normal IPv4 addresses. It will be interesting to see whether Davies prediction pans out as it might catch some ISPs off-guard, although there's really no excuse for ignoring years of warnings.

Thankfully IPv4 does have a replacement, IPv6 (e.g. 2ffe:1800:3525:3:200:f8ff:fe21:67cf), which is longer and more secure by design. Sadly many broadband ISPs, hardware (routers etc.) manufacturers and software developers have been slow to upgrade their networks and services.

The loss of new IPv4 addresses will certainly not destroy the internet, although network operators that don't properly support IPv6 would find it hard to add new connections (i.e. customers). Likewise some end-users might experience connectivity headaches when they realise that their router doesn't support it.


Some ISPs could attempt to stave off the problem by using IPv4 address sharing, although that carries with it an array of its own performance, security and connectivity issues. Either way the Internet will run out of free IPv4's within the next few weeks, although the addresses will continue to be used for many years to come (due to the needs of legacy hardware and software etc.).

UPDATE 28th January 2011

We are now hearing from sources inside several UK ISPs that Monday 31st January 2011 will see the last 'normal' IPv4 address blocks being allocated, which will trigger the remaining blocks to be allocated as well.