How much is your IPv4 Space Worth

Published: 2015-06-10
Last Updated: 2015-06-10 17:52:33 UTC
by Johannes Ullrich (Version: 1)
4 comment(s)

Thanks to Rob for reminding me of IPv4 auction websites again. I looked at them a couple years ago, but there was very little real activity at the time. Looks like that has changed now. ARIN is essentially out of IPv4 space, and very restrictive in handing out any addition addresses. It has gotten very hard, if not impossible, to obtain a larger block of IPv4 space. So no surprise that markets for IPv4 space are coming up. 

These markets are not in line with registrar policies [1]. If someone receives an IP address assignment, then they don't technically "own" the addresses. Once they are no longer needed, they are supposed to be returned to ARIN to be handed to the next applicant in line. But there has been little enforcement, and there have always been grey areas. For example, a company may buy another company, and in the process obtain access to that companies IP address space. Later, assets other then the IP address space could be sold off, leaving the buy with the rights to the IP address space.

Here are some of the sites offering IP address space (I am not endorsing them, and have no idea how "real" they are):

- Currently three offers for space up to a /20 at $7-$10 per address. There are a couple of bids.
- There are a number of auctions with IP addresses for sale and for rent. Looks like they are going for about the same price as the addresses at [2]

Some sites have dones so in the past, but already shut down (e.g. In other cases, the nanog mailing list was used to offer IP address space, or IP addresses were purchased as part of bankruptcy auctions [3]


Johannes B. Ullrich, Ph.D.

4 comment(s)


Last I knew you needed a class C to get an AS and use BGP (at least from the primary ISP). At least that has been what I have been doing for the last 8 years.

Can anyone clarify?

I am wondering if Apple Computer has returned any of the IPv4 addresses it has had from the early days of the Internet. Ditto MIT, DEC, HP, Xerox, IBM, Ford, GE & others with their own /8 blocks. I wonder if they are planning to sell any of them?
Forgive me for the off topic post. Are you at the facility on the other side of the solar system, Johannes? I'm having some kind of time zone issue because my browser shows that you posted this four decades ago.

Update 2015-06-11 15:15 UTC
Well, it now says the original post was made 21 hours ago. Must have been a glitch in the matrix.

At least in IBM's case, it would be a massive undertaking (and expense) to clear out the space to give some of it back. Probably not gonna happen. I for one am glad that we're finally running out of IPv4 space, so that we can start moving to IPv6 and stop treating address space as a rare commodity.

I mean, think about it for a minute. We're doing all sorts of strange things to "conserve" address space because we've basically RUN OUT OF NUMBERS? There are countably infinite many of them, for pete's sake. NAT, 6-7 different sizes of subnets in regular use, address allocation schemes complicated enough to require large spreadsheets to remember that this physical site is composed of the following completely unrelated /24s, etc. I could have stopped at NAT, of course.

I say burn up those IPv4's as fast as you can so that everyone has a reason to move. At some point it will be cheaper for the average organization to move to IPv6 than to keep buying address space allocations, and just have a handful of public-facing IPv4s for their most popular services for non-IPv6 capable clients.

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