There have been voices raised that we are running out of IPv4 addresses for some time now. So who has taken them? After discussing this at a coffee break here at Pingdom, we were curious. Are there are any “big spenders” who have allocated a huge share of the IP space for themselves? Yes there are.

When looking at the assigned IP blocks at IANA (Internet Assigned Numbers Authority), what becomes immediately clear is that the US Department of Defense has a significant number of large IP blocks. We only looked at /8 IP blocks, the largest blocks you can get, and there are 12 of them assigned to the US DoD and related organizations. Each /8 block holds 16,777,214 IP addresses, so the DoD have in effect allocated more than 200 million IP addresses. That should hold them for a while.

The closest any other corporation comes to this are Level 3 Communications and Hewlett-Packard, with two /8 blocks each. The DoD-owned IP blocks together with the 26 corporations and universities who have their own /8 blocks hold more than 671 million IP addresses.

These were all early land grabs, most of them made between 1991 and 1995.

Some notables among the companies with one /8 IP block are Apple (but no Microsoft in sight), IBM, Halliburton and the Ford Motor Company.

Companies and organizations with IPv4 /8 blocks from IANA Owner Blocks ~IP addresses US Military (Department of Defense etc.) 12 201 million Level 3 Communications, Inc. 2 33 million Hewlett-Packard 2 33 million AT&T Bell Laboratories (Alcatel-Lucent) 1 16 million AT&T Global Network Services 1 16 million Bell-Northern Research (Nortel Networks) 1 16 million Amateur Radio Digital Communications 1 16 million Apple Computer Inc. 1 16 million Cap Debis CCS (Mercedes-Benz) 1 16 million Computer Sciences Corporation 1 16 million Deparment of Social Security of UK 1 16 million E.I. duPont de Nemours and Co., Inc. 1 16 million Eli Lily and Company 1 16 million Ford Motor Company 1 16 million General Electric Company 1 16 million Halliburton Company 1 16 million IBM 1 16 million Interop Show Network 1 16 million Merck and Co., Inc. 1 16 million MERIT Computer Network 1 16 million Massachusetts Institute of Technology 1 16 million Performance Systems International (Cogent) 1 16 million Prudential Equity Group, LLC 1 16 million Société Internationale De Telecommunications Aeronautiques 1 16 million U.S. Postal Service 1 16 million UK Ministry of Defence 1 16 million Xerox Corporation 1 16 million 40 671 million

The table doesn’t include the blocks allocated for RIRs and other special purposes.

One thing that strikes you is the low number of ISPs on this list. This is most likely due to their late appearance on the internet when it was harder to reserve big IP blocks, forcing them to settle for smaller blocks.

That the US Department of Defense has such a huge amount of the IPv4 address space is partly due to historical reasons: They developed the internet in the first place (ARPANET) and have a strong vested interest in the evolution of the internet.

Of course, IPv6 is on its way which will end this discussion for good (or at least for a looong time), but with a bit of rearranging IPv4 could probably last us for quite a while yet.

A small note:

We only looked at IANA’s own numbers. We didn’t look at the Regional Internet Registries such as ARIN or RIPE, partly to limit the scope of the research and partly because we were only interested in the huge /8 IP blocks. There are only 256 /8 blocks, and many of these are reserved for special purposes.