The Internet Assigned Numbers Authority (IANA) recently allocated its remaining normal blocks of IPv4 internet addresses to APNIC in Asia. Now all that's left is for the last blocks to be simultaneously distributed to the five Regional Internet Registries (RIRs); a date for that is expected to be set today (prediction - March 2011 see update at the bottom).

Today's forthcoming announcement is effectively the last nail in IPv4's proverbial coffin, although it will admittedly take a couple more years before ISPs around the world have completely depleted the RIRs remaining addresses.

Suffice to say that the situation has caused a great deal of media confusion, not to mention some completely inaccurate reports, about what this event could mean for the internet. We explored some of the concerns in Mondays news (D-Day - Last Remaining Normal ipv4 Internet Address Blocks Finally Allocated).

One of the biggest concerns stemmed from a lack of IPv6 support by some of the UK's leading broadband ISPs. Providers that cannot support IPv4's replacement could have trouble adding new customers in the future and may even face connectivity or performance problems. Thankfully most have since told us that resolving this difficulty is a priority.




Sadly many ISPs, especially larger providers, were unwilling to talk with us about the situation. We weren't surprised by that, especially when most will only privately admit to having no near term IPv6 support prepared. Part of the reason for this is alluded to in several of the ISP comments (above).

The biggest problem for most consumer facing broadband providers is a lack of affordable, IPv6 supporting end-user (customer) connection hardware (routers, modems etc.). Most ISPs claim that there are virtually no low-cost IPv6 supporting consumer routers available and the manufacturers are only just waking up to the problem. Meanwhile others, such as Virgin Media UK, have support for IPv6 in their newest (D3) cable routers but not the old ones.

In fairness this is partly because too few of the largest ISPs, some of which have plenty of spare IPv4 addresses (enough to last them for a good few years), have as a result not been bold enough in requesting IPv6 support from the manufacturers. There's much more choice at the business end.

Ultimately no competent ISP would want to put itself into in a position where the addition of new customers is not possible. Neither would any credible ISP allow addition of new users to only be viable through half-way measures like IPv4 address sharing, which carries with it all sorts of connectivity and performance problems.

Never the less, IPv4's final address block allocation is the signal for all ISPs to get themselves prepared for an inevitable future. It's costly to run dual stack IPv4 and IPv6 networks side by side and eventually they'll want to get rid of IPv4 altogether, but that won't happen for quite a few years yet (it would cause far too many problems with older software and devices).

In the meantime consumers probably don't need to worry. The transition from IPv4 to v6 should be fairly seamless and with any luck you won't notice it happening at all.

UPDATE 3:28pm

IANA has just officially handed over the last remaining blocks (102, 103, 104, 179 and 185) of IPv4 internet addresses to the five regional registries.


Six months is possible but markets do vary and some estimates say up to two years. Either way, it's good to be prepared.