Do you have an “After IPv4” Plan?
August 19th, 2010For some time I have been predicting that the “heat” around IPv4 exhaustion and IPv6 deployment will go up dramatically when the IPv4 exhaustion story goes mainstream – out of the Tech press and into the Wall Street Journal, or MSNBC. To date, concern about IPv4 has been building slowly, with some organizations actively deploying (few, and almost entirely carriers), more “planning, but going slow” (the rest of the carriers, government), and even more “tracking” (all other organizations) – where “tracking” means they’ve heard about it, but are unconcerned.
This is going to change when the WSJ runs a story like “DSL Provider Misses Earnings Projections – Cites Non-Availability of IP Addresses”. At that point, more business leaders will ask their CIOs what their own status is – and having a good story will be important. To have a good story ready, a CIO needs to have a plan, and have thought through that plan to make sure it is achievable. If not, then the CIO needs to go back in time and get cracking. In a world where time-travel is not yet commonplace, at least the CIO needs to get cracking now – and with conviction. As a moving-towards-mainstream example, National Public Radio (NPR) ran a story on IPv4 exhaustion in August of this year “IP Address Shortage Has ISPs Scrambling For Space” on their “Weekend Sunday” radio program – it is not quite the WSJ – but it is not way-tech CNET News either (http://www.npr.org/templates/story/story.php?storyId=128907099).
How close to that headline are we? Closer. Quite close I think. Consider:
Currently, IANA (Internet Assigned Numbers Authority) holds 14 “/8s” of unallocated space, out of a possible set of 256 “/8s” (so one (1) /8 equals 1/256th of the entire IPv4 address supply) (note that a “/8” is a large chunk of addresses suitable for IANA to assign as a regional block, which is then divided further and assigned to carriers and large enterprises).
In 2010 (and it is only August – not December), IANA has made these assignments – ten (10) in all:
- APNIC, January (Asia-Pac)
ARIN, February (North America)
ARIN, February (again)
APNIC, April
APNIC, April (again)
RIPE, May (Europe, Middle East)
RIPE, May (again)
LACNIC, June (Latin America)
APNIC, August
APNIC, August (again)
(Note that AFRINIC – Africa – did not receive any allocations in 2010)
(For more details see http://www.iana.org/assignments/ipv4-address-space/ipv4-address-space.xml)
Per IANA and the NRO (Number Resource Organization - another organization involved in IP address assignment), the last five (5) /8 blocks will be given out – one to each of the five (5) registries – immediately when the 6th to the last /8 block is given to any registry – in other words assigning the 6th to last block triggers final, close-out allocations(For the entire policy see http://www.icann.org/en/general/allocation-remaining-ipv4-space.htm)
(Diagram from http://www.iana.org/numbers/) So, not doing any advanced math, if IANA handed out ten (10) /8 blocks in 7 ½ months in 2010, then the 6th to last – and by definition *ALL* the remaining IANA-held blocks – should be gone in ten (10) months – June 2011. (This rough analysis is consistent with a much more analytical discussion maintained by Geoff Huston at http://www.potaroo.net/tools/ipv4/) That sounds soon to me.
Consider this yet another “call to action”. This one is a little different. It does not call on CIOs to deploy IPv6. It calls on CIOs to plan a strategy for IPv4 scarcity, followed by IPv4 exhaustion, throughout which the business can continue to earn, grow, and thrive. Extending IPv4 services via some kind of Large Scale NAT (LSN) might be part of a near-term strategy, and IPv6 deployment will almost certainly be the mid and long-term strategy.
Any CIO that hatches a (hasty, ill-conceived, incomplete, somewhat desperate) plan the morning of the WSJ article can’t say they didn’t have some warning.

It was half a decade in the making (2005) , but the 





