Anyone know what IPv6 adoption is looking like these days? Google is showing like 3% of their connections are native to it [1], which does not look promising.
1: https://www.google.com/intl/en/ipv6/statistics.html#tab=ipv6...
10/8 is off limits, but there are a bunch of /8 blocks which could likely be reclaimed if we really needed to, including:
- About half a dozen which were allocated to the US military in the early 1990s, most of which aren't even publicly advertised at all
- 44/8, reserved for amateur radio
- A number of other /8 blocks owned by corporations, which could potentially sell or return chunks of them if properly convinced
Edit: I wish there was an updated version.
That's enough to find out that this particular one is called a Hilbert curve.
This page has similar images from 2012
As for 44/8, there are still those that use it, taking it away would mean having to renumber all of the equipment on that network...
No, trying to reclaim IPv4 addresses by making people go through herculean efforts to renumber their networks is not the way forward and simply delays the inevitable. IPv6 is the way forward, start pushing that, and get more people using it.
Consider subcontractors needing to connect to servers in a particular department.
Ford has 181,000 employees as of 2013 (http://en.wikipedia.org/wiki/Ford_Motor_Company).
That's very roughly 92 publicly routable IP addresses per employee.
I highly doubt they need that many.
It would take years to arrange the return of 100 million addresses compared to the demand for a few billion addresses with even conservative growth.
Well before that, you could recover 18/8, MIT's prefix; how many addresses does a single university actually need, even MIT? Stanford already returned their /8 prefix. Or you could potentially recover a variety of DoD /8s, or start assigning some of the ones that are "reserved for future use" like 240/4.
Of course, an even better use of 240/4 would have been to use it as a backwards-compatible way to move to a larger address space. IPv6 should have been specified with IPv4 compatibility via NAT from the beginning, so that it could be a gradual migration. I mean, we're moving that way anyhow, but with a much more painful period in the middle in which NAT is necessary but IPv6 isn't ready yet for people who want to end the pain of NAT.
The 240 block is problematic because a huge amount of legacy routing equipment is hard-coded to blackhole it. The best thing for it is probably to reserve it for unspecified local use, which would allow you to use it to NAT IPv6 addresses into locally, or use as additional RFC1918-style address space, or as ORCHID-style address space for IPv4-only applications using the likes of cjdns, etc.
http://www.internetsociety.org/deploy360/ipv6/statistics/
Eric Vyncke and Lars Eggert have two good sites at:
https://www.vyncke.org/ipv6status/
https://eggert.org/meter/ipv6.html
Cisco 6Lab has a nice map at: http://6lab.cisco.com/stats/