There were several really interesting topics discussed at last weeks IPv6 Summit in Canberra, when I can find the time I’ll write up a little more detail on some of the ideas that I think could really drive breakthroughs in IPv6 adoption.
One of the topics that I thought was interesting, but more questionable, was the idea of a secondary market for existing IPv4 addresses.
It is a given that there are only a finite number of IPv4 addresses available, and according to current estimates about 500m of those addresses remain available for new companies or individuals wanting internet access, no where near enough to connect the 5bn people who currently have no internet access or the array of internet connected devices that are appearing in the marketplace, by current estimates the remaining addresses will only be enough to see through to somewhere around 2012.
The assumption is that once there are no new IPv4 addresses available then one way to connect yourself or your company to the existing ~1bn internet users would be to buy yourself an address block from somebody who was willing to give theirs up.
Discussions in the room at the Australian IPv6 Summit suggested that blocks of address may start to change hands at costs of around US$1000 per address, and while that sounds like a lot it is not really all that expensive for a corporate or a government who are looking to keep their systems online and accessible.
I don’t think there can be any debate that such a market will exist at some point, but I have to wonder how long it would exist for and what the real value of an IPv4 address would be. Obviously the answers to both questions revolve around how much IPv6 deployment there is at the time, and how many services you can reach using just an IPv6 address.
The first point that goes through my mind is that the users who give up their IPv4 addresses have to go somewhere, and the only logical destination at this point would be onto the IPv6 network. Every user that moves in this manner increases the value of the IPv6 space, and in turn decreases the value of the IPv4 networks as the number of active users and services diminishes.
Another possible source of IPv4 address space that could appear on the market would be the vast number of addresses that are allocated today but are not in use. What isn’t clear to me is who this allocated but unused address space really belongs to. I have to wonder how complicated it would be to return these unused addresses back to the unallocated pool for reallocation on a free and fair basis.
Setting that question aside and looking only at the idea of a value being placed on an internet address I think the debate becomes even more worrisome. At a minimal cost of a few dollars for an IPv4 address there is an implicit decision about who can and cannot benefit from internet access. If this type of secondary market did exist then multinational corporations would see little or no effect other than building the sum into the financial model that that represents their operational costs. The story would be different for an individual in a rural part of a developing nation however, where placing a cost on address space would move internet access just one more significant step further out of reach.
When I look at just these small parts of the debate, while I don’t doubt that this type of market will exist at some point, it does seem very short sighted given the diminishing number of users, and therefore benefit, that we will inevitably see on the IPv4 network, along with the obvious social cost of excluding many of the 5bn people in the world who don’t have internet access today.
Nations like India and China will inevitably be forced to bring upwards of 2bn users onto the IPv6 network, there just isn’t enough IPv4 address space available for them to connect their citizens any other way. This should provide more than ample business justification for dual hosting sites delivering commerce and services onto both IPv4 and IPv6 networks, from both commercial and government providers.
To me at least, it seems to make far more sense for ISPs, commerce and service providers to commit to finally making the switch to a new protocol that can meet today’s needs rather than finding temporary solutions to problems that will eventually have to be resolved whatever we do.
I thought I understood this stuff, but I can’t understand why there’s such a flap when there’s NAT and 64k ports per IPv4, not to mention the time-slicing effect of address leases (which I just mentioned).
NATs are at best a short term answer… a couple of obvious issues with them.
Applications needs to be NAT aware, it isn’t hard to do but it is an overhead. In a few high volume research environments the overhead starts to become significant, when you should be focusing on moving data between nodes you find yourself focusing a percentage of your bandwidth on NAT related hygine issues.
Part of that NAT hygene involves keeping the connection alive, which needs data to be send at some timed interval to ensure that your NAT enabled port stays enabled. For mobile devices this would mean that you would have to keep the radio turned on and sending data that has no real user value – draining the battery for the sake of the network rather than for the sake of your application.
That is an issue for a mobile phone, but imagine a sensor device running off a small bit of captured sunlight and you start to have real limitations introduced by a lack of avaiable running time and power. Part of the IPv6 dream is to network enable millions of devices, and for that we need direct connect (read non NAT) connect to help with the power questions.
Several of the big routing vendors are being pushed to look at “carrier grade NATs”, technology that is similar to your $100 home router but capable of managing several hundreds of thousands of NAT enabled connections. While that would provide a comprehensive answer to how much address space each ISV or carrier required for their users, it would introduce several restrictions for those users around how they use the bandwidth that they buy from the service.
NATs are a clever answer to a complex problem, but come with their own costs… they also limit the scenarios that we can build and deploy devices to support.
> Applications needs to be NAT aware
It feels a bit like the old times except with me now seriously outgunned. I’ve been responsible for quite a few web applications and never made a single one of them NAT-aware.
> Part of that NAT hygene involves keeping
> the connection alive
Isn’t the idea of a connection that it doesn’t need to be alive? This sounds more like someone trying to keep a session alive, which is a different thing that’s wholly and acceptably up to the application. New ports every time is fine for a connection, unless someone has done some daft things with the application’s security.
You don’t have to rely on an IP address to guarantee who you are, and pretty much no sensible application does. Nor does your solar-powered gadget need to post crap through NAT to keep a session going. It just sends a cookie, a session ID, or whatever you want to use instead, next time something needs to go across the network.
Or am I, apparently like the rest of your world, missing the point?
Probably the library you were using was helping you out, or the nature of your particular app meant that it didn’t matter.
For the example of a network enabled sensor, there is a good chance that you would be running so little code that there would be no cookie, session ID or any of the other elements that you would find in a conventional web app.
a little more reading;
http://en.wikipedia.org/wiki/Network_address_translation#Drawbacks
http://en.wikipedia.org/wiki/NAT_traversal#The_NAT_traversal_problem
There is no debate that a NAT solves a lot of problems, but it will also introduce a couple of new issues for you as well in specific scenarios.
If you want an easier way of thinking about it, try this… for any technology that you want to scale up for use by a potential multiple billions of people, the simpler you can make it the better.
OK, I know of addresses that the owner would like to sell. Where can they be sold?
Thanks,
Jon
That is a good question Jon. As far as I’m aware we have yet to see a marketplace emerge.