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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
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.