This is a honest question. I would like to know how we avoid ending up in a world where a few large companies control all the available IPv4 addresses (which they don't really need) so they can rent them to the rest of us at exhorbitant prices.
IPv6 won't render the problem moot - it's likely that IPv4 addresses will remain a necessity for globally reachable services for years to come, regardless of IPv6 adoption.
I guess that when IPv4 addresses are traded in a free market it is easier to realise the cost of not adopting IPv6, eventually leading to a faster adoption (which is a good thing for everyone, NAT is essentially making the internet a lot less cooler place than it could be).
Also, what would the alternative be? Just not handing out IPv4 blocks to new players and telling them "tough luck"? Or a lottery? I really don't know a better alternative to a free market.
My honest (though possibly unpopular) opinion is that the incentive should have been given years ago through government intervention, by legally compelling ISPs to provide IPv6 connectivity to their customers. If most of the Internet had been switched to IPv6 by now, no bidding war over IPv4 addresses would need to take place.
Naturally, it's moot to point out what could have been done and wasn't. But I think this illustrates a limitation of market-based incentives: they seem to work well on the short term, but have a tendency to fail on the long one. Slow IPv6 adoption is, in my view, a market failure that should have been corrected through government intervention.
Do you like, have several IPv4 addresses assigned to you or something?
I can see the advantages, but do I want my devices to have publicly routable addresses? I prefer that the public Internet doesn't know the exist and can't easily contact them without receiving a recent outbound connection. (Perhaps I missing an obvious solution here?)
There seems to be this common misconception that a firewall and a NAT box are the same thing, but they're not. It just happens that most NAT implementations also work as firewalls (though not the other way round).
Even if you don't have a firewall, the odds of someone discovering your IPv6 address by chance (i.e. without you communicating with them first) are incredibly low. Common IPv6 deployment practice is to delegate at least a /56 prefix to each end user, so your device gets an address chosen at random from 2^72 possibilities. You can even hop into a different address every few minutes for added security (some IPv6 stacks do this).
So please don't spread the misconception that IPv6 is somehow less secure than IPv4! :)
I'll address the technical issues in my response to the other commenters response.
Once a private device communicates with a public Internet server, won't that server and every network between it and the private device (my ISP, etc.) know a publicly routable IP address on my private network? I know a firewall could still help protect it (simple SPI, for example) but having a publicly routable IP would seem to simplify the attacker's job, and possibly reveal information about specific devices and users (i.e., track who is doing what).
Also, I assume my firewall's public IP must be on the same public subnet as my internal devices. It doesn't seem like it would be hard to guess the addresses of devices on the private side.
I haven't looked at IPv6 much, so again I suspect I'm overlooking something basic.
> If your firewall (which you'll still need) is configured correctly
In my experience, this situation isn't common -- especially among end users but even among professionals.
Regarding the tracking of specific users: RFC 3041 stateless autoconfiguration (which is deployed at least on Linux and OSX - not sure about Windows) allows a device to switch to a new random IPv6 address within its assigned prefix every few minutes. This mitigates, though it does not eliminate, an attacker's ability to correlate connections originating from the same device over a period of time.
Naturally, all of those addresses will share a common IPv6 prefix. But that is no different from most residential NATs, where all connections are observed from the outside to originate from the same IPv4 address.
Also due to stateless autoconfiguration, guessing the address of a device from the outside is equivalent to finding a needle in a 2^64-straw haystack. It's not impossible, but it takes time and a lot of traffic to do so.
This would raise prices (in the event that is really desired) while avoiding squatting and rent seeking.
For example a power company I know about. The operators there decided to use public addresses for the power control/monitoring network instead of 10/8 to be sure of having unique addresses, even in case of a merger or cooperation with another power generator.
IANA specifically states that a free-market of IP addresses would be harmful, instead they argue that IP allocation should be based on need and not treated as property.
>ISPs are required to utilize address space in an efficient manner. To this end, ISPs should have documented justification available for each assignment. The regional registry may, at any time, ask for this information. If the information is not available, future allocations may be impacted. In extreme cases, existing loans may be impacted. RFC 2050
Big companies have fought them on this and won.
>The court held that Nortel had an exclusive right to use the legacy numbers. The court also explicitly sanctioned Nortel’s exclusive right to transfer its exclusive right to use the numbers. In recognizing Nortel’s exclusive right to use legacy IPv4 numbers, the court implicitly found that Nortel had the exclusive right to possess the numbers themselves. Consequently, Nortel could exclude others from possession and use of the same legacy IPv4 numbers. In other words, the court found Nortel possessed the customary “bundle of rights” commonly associated with the ownership of tangible or intangible property. - Property Rights in IPv4 Numbers: Recognizing a New Form of Intellectual Property
Which isn't to say that any initial allocation will satisfy us as fair or that the outcome will satisfy us as fair, but a top down system may well end up being neither fair nor efficient.
Also, we're currently in a world where no large company owns even 1% of the addresses, and heading towards one where IPv6 is the majority of traffic. Have a look at http://www.google.com/intl/en/ipv6/statistics.html and pretend to be an IPv4 address investor. The year-end figures are about 0.4, 1.0, 2.5 and 5.7%, so a little over 100% yearly growth for each of the past three years. If that goes on, we'll pass 50% IPv6 in 2017, and if that happens I rather doubt that IPv4 addresses will be worth much.
Of course that projection doesn't have to be right. Perhaps IPv6 growth slows down. But if you were an investor, would you invest heavily in v4 addresses on the assumption that IPv6 growth slows down? If so, why do you assume it'll slow down?
Oh, and I do think IPv6 will render IPv4 moot. Assuming that trading goes on, IPv4 will increasingly use tunnels and long-prefix routes, and then it'll have the kind of reliability problems v6 had around 2005.
Compared to a world where you can't get IPs at any price? Seems pretty obvious: you can get IPs.
I would like to know how we avoid ending up in a world where a few large companies control all the available IPv4 addresses (which they don't really need) so they can rent them to the rest of us at exorbitant prices.
It seems like the cloud is already going there with only a few large providers. All I can suggest is to buy your IPs now before Amazon does.
You seem to be presenting a false dichotomy; there are plenty of intermediate solutions between the current state of affairs and a laissez-faire market. At the very least, if we're going to set a price on IPv4 addresses, I think it should be set by the RIRs - not by the companies to whom they were allocated. (Remember that RIRs have the right to reclaim addresses that are not being used.)
In other words: my concern is not that IPv4 addresses end up having a price tag on them; that seems inevitable at this point. My concern is that big players might be able to dictate the prices and effectively buy the small ones out of the Internet.
EDIT: Fixed the number of addresses in a /18
Another point to consider is that there are things you can do with IPv6 connectivity that are very difficult/costly, or outright impossible, in NATted IPv4 land.
Personally, I'm waiting for the next generation of peer-to-peer protocols that make use of end-to-end IPv6 connectivity instead of hole-punching and proxying through third-parties. (Case study: ever thought how ridiculous it is that in 2015 it's still non-trivial to send a large file to someone over the Internet without using some sort of storage service?)
It's plausible that one of those new applications could end up being the "killer app" for IPv6.
The problem is that IPv4 is not forwards-compatible.
The US Army in various guises controls vast swathes of address space, but there are also lots of corporations with a 256th of IPv4 all to themselves: Halliburton, GE, Prudential, Ford, etc. MIT also appears to be the last university still hanging onto their own block.
For example, lets say you wanted 18.104.22.168. That's controlled by hostwinds.com, which offers VPS hosting. There doesn't seem to be anyone on that IP address. The reverse DNS lookup makes it appear that it's in their normal client space. A phone call to the right person there might get you what you want.
There have been periods of time where various providers had filters (in certain ranges) to prevent routing table bloat.
If the first octet of the IP address that you want is in that list, it's probably owned by someone who isn't selling.
Of that list, I can actually see the DoD needing 240M IP addresses.
Is it so you can communicate with servers or clients that don't facilitate any form of IPv6?
For most consumers IPv6 will already work on many sites, and I expect that to increase considerably over the next 1-2 years.
Having multiple IPv4 addresses helps to alleviate that problem.
IPv4 address also has reputation attached to it.
That reputation is much move valuable that reputation on IPv6 address, because cost of IPv6 is pretty much zero, but IPv4 costs $10+ per address.