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IPv4 vs IPv6: The Road Ahead
jeffy124 writes "With the world moving towards having every device under the sun being Internet-connected, is the Internet going to be too large? This article off CNN.com examines this potential situation. They look into the problems of switching networks from IPv4 to IPv6, and the inclusion of inter-operability between the two. Benefits of moving to IPv6 are looked at, but so are the critics of it who point out that if we don't have a problem now, why fix it? While low of technical details, the story points out that not many systems out there currently support IPv6. "
if we don't have a problem now, why fix it?
(ahem)
"640 kB should be enough for everybody"
"I see a worldwide market for 5, maybe 6 computers"
and one that I can only assume:
"yeah, use 2 digits for the year. Bah, the year 2000 is 20 years away, nobody will be using this stuff then anyways"
And besides, if you wait until the problem is upon us, it'll be too late to fix it.
If God gave us curiosity
Why not run the conversion like the 6bone has? That is, start off with virtual IPv6 between IPv6 supporting sites over IPv4 links, and gradually shift to native IPv6 where possible as more and more of the intermediate "link" sites convert to IPv6? At some point, you switch over core routers one by one so that they're running virtual IPv4 over IPv6 transport, and switch out the last of the IPv4 hardware as it becomes obsolete.
Not that this necessarily provides an incentive for IPv4 users to switch, but IMHO, as a person that's not too knowledgeable about IPv6, I don't see why technically a migration has to be too difficult. Maybe you could make the incentive something like rewarding you with more IPv6 addresses as you move out of IPv4 space - that would definitely move big network operators along, at least.
I'm still not sure how to force a more equal global assignment of the dwindling IPv4 address space. It seems like if the IPv4 afficianados aren't careful, China will just switch to IPv6 immediately, and the rest of the world will get dragged along just so we can continue to communicate with that huge percentage of the human race.
Your right to not believe: Americans United for Separation of Church and
good IPv6 homepage
IPv6 HOWTO
IPv6 Standards
IPv6 Tutorial (PDF)
And the 6bone
Linux: Because a PC is a terrible thing to waste.
James Brents
Will it give back that huge class A domain that MIT still has?
A class A is 1/20,282,409,603,651,670,423,947,251,286,016th of the total IP6 namespace. Why not let them keep it?
Network Address Translation only provides one-way connectivity. It allows a system behind a NAT to establish connections from external sites and retrieve data.
What it *doesn't* allow is anyone out on the internet to go and connect to the machine behind the NAT, which is kinda essential for anything beyond web-browsing.
The internet is not just port 80. Many people treat it as such, and I hope they have fun. But don't delude yourself that you have a full internet connection, because you don't. You've just got a fancy TV with a few more channels.
NAT is a stop-gap measure at best. IPv6 is essential for allowing the internet to scale the way you want it to.
Think about it: it's not outrageous that MIT and similar institutions have class-A networks - it's outrageous that *you* don't. IPv6 can fix that.
Ask your ISP about their plans to upgrade to IPv6 - and what their IP allocation policy will be. If the ISP doesn't intend to give you lots of IPv6 addresses, start looking somewhere else.
Dynamic IP allocation sucks in the same way that NAT does. Many of the peer to peer projects nowadays, in order to keep functioning, have to build their own namespace and addressing structures just to work around it.
The theory behind all this is that you can then move a device from one network to another, without ever having to worry about routing problems, IP numbers colliding, or other such mundane trivia.
"Permanent" addresses, in this system, don't exist. They're all calculated.
How does this work, in practice?
Well, let's say that Joe Bloggs is connected to AOL. AOL decides that the backbone provider it uses can get stuffed, and switches. This changes all of AOL's addresses, and therefore Joe Bloggs' address.
However, because addresses have a lifetime attached to them, the old address remains active (although forwarded) for a finite length of time, although new connections to the old address are prohibited.
Because of this, it makes no sense for some central registry to store AOL's IP number. It can change once every 60 seconds, along with the IP address of everyone/everything connected via it.
The only person who can meaningfully store AOL's IP address becomes AOL, itself. Nobody else can possibly know it, with any reliability.
Normally, ISPs and large corporations aren't going to flip around like that. But they -can-. The protocol permits it. Because of that, and because uptime is increasingly important, they will then be able to shop for a secondary provider for a backup link, in case the first one dies.
In IPv4, a backup link via an alternative provider would be lethal. There would be no way to handle the changes in addressing, unless the entire ISP or company was behind a NAT system with High Availability at the IP level, which causes its own problems.
With IPv6, the change-over would take under 5 seconds for the whole of AOL. Nobody would notice the delay, nobody would get disconnected, and the whole setup is much simpler.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
From what I understand, Linux and Windows NT have had IPv6 support for quite some time now.
The problem appears to be more subtle than that. The routers are mostly compliant, I wouldn't worry about it.
The smooth transition is going to require that everyone on the 'Net start to switch over. Even half-wit Windows-95 AOL-point-and-drool users.
Surely, we can release patches to the operating systems. And users can upgrade to new applications programs which aren't crashing when they request a DNS lookup and get something longer than they expect.
But you know they won't.
As evidence, I submit to you the Code Red worm. You'd have to be living under a rock for the past two months to not know about it. Yet, I still get hit by infected machines. Follow the link on my .sig.
I haven't studied or attempted to deploy IPv6, but it will have to be backwards compatible with IPv4.
In the 1950s, Europe upgraded their TV system to color. The new PAL and SECAM color standards weren't compatible with their old 405/441-line black and white standards, leaving consumers with far too many confusing choices. Arguably, European TV never recovered.
By contrast, RCA came up with an ingenious way of making a color signal ride on top of the existing North American black and white system. Old black and white TV sets were eventually replaced with color, but there was no great format change. You bought a color TV or a black and white set, and you weren't at the mercy of finding out whether or not there was still a black and white station in your area. People transitioned more gently and weren't put off by having their two-year-old oak-cabinet investment turned into a paperweight by moving out of a 405 line service area.
IPv6 will have to be deployed in the same way or adoption rates will wane.
Fire and Meat. Yummy.
According to the RFC's, even a lowly dialup users will be given more routable addresses than the
entire internet contains at the moment.
How about a killer app? The problem is that right now if you start using ipv6 you are pretty much alone. Actually you might as well unplug your network cable, since you won't be able to do much useful stuff with it.
What is needed is ipv6 only services (e.g. mp3 peer2peer filesharing) AND an easy way to get an ipv6 number for your clients/servers that can coexist with your current ipv4 number (i.e. your computer has both an ipv4 and ipv6 number). The easy part is essential because that prevents that people start creating ipv4 gateways to such services (thus removing the need for getting an ipv6 number). There are plenty of ipv6 numbers available so getting and registering one should be made as easy as possible (something like a distributed, global dhcp server that would automatically get you one based on your mac address would come in handy). Come to think of it, why not just automatically convert those mac addresses into ipv6 numbers (mac addresses are supposed to be unique anyway but I'm not entirely sure this is a great idea)
As I understand it, ipv6 can be tunneled over existing ipv4 networks, so it shouldn't be a problem if some routers inbetween ipv6 hosts are ipv4 only.
This would cause the amount of client pc's with ipv6 numbers to gradually grow. Also since lots of PCs don't have static ipv4 numbers, the amount of servers on ipv6 would also grow. Eventually, there will be a critical mass of ipv6 servers and clients and the switch can be made.
Currently there are a lot of p2p applications in development. I imagine, implementing such stuff would be a lot easier using ipv6 with its improved features. Another killerapp could be streaming multimedia (you want to see this great movie, get yourself an ipv6 number now!!).
Jilles
You're thinking about this completely wrong. What was it that made TCP/IP the 800 pound gorilla standard in the first place? The US Government, especially the military, standardized on it. What we need is to get the US Government to start requiring IPv6 in contracts.
--
"Open source is good." - Steve Jobs
"Open source is evil." - Microsoft