[tgflynn]

Yes, but I don't think comparing Internet adoption with IPv6 adoption is terribly valid.

The first was a radically new technology and it took years for people to figure out how to best make use of it.

IPv6 was supposed to be a purely technical improvement to deal with some deficiencies of IPv4, notably address space limitations. It should mostly concern only network and systems administrators and systems software developers and be largely transparent to end users.

It's interesting that the two seem to have similar growth curves, but given the very different audiences involved I'm not sure what to make of that observation.

Certainly if you asked knowledgeable people in 1996 how long it would take to achieve near 100% IPv6 adoption I doubt many would have predicted 20 years.

On the other hand in 1981 I suspect few would have predicted that a technology developed by DARPA would be used by people in 2000 to buy books and manage their bank accounts.

[runeks]

> It should mostly concern only network and systems administrators and systems software developers and be largely transparent to end users.

I'm no network engineer, but as I understand it, to support IPv6, companies need to replace their switches. I think it's fair to say that there are literally millions of switches that need replacing. We are talking billions of dollars in total investments. I really don't see how it's surprising that this will take a while. Billions of dollars don't hang on trees, companies need to earn the money before they can spend it.

At the same time, because IPv6 is used less frequently, it is more expensive. The price of electronics is determined by volume: the more you produce the cheaper it gets. This means IPv6 has a price disadvantage to IPv4, which is especially noticeable in the early years (of ~0.1% adoption). A device that is produced at only 0.1% the volume of the most popular devices will be considerably more expensive.

This is, in part, why we see an exponential adoption curve: the more people who buy IPv6 equipment the cheaper it gets, and the cheaper it gets the more people buy it, this chain reaction helps to cause the exponential adoption rate.

I'm not saying everyone will end up using IPv6, although I think it is likely, but I'm saying it should be no surprise that replacing billions of dollars worth of network equipment takes time.

[_cbdev]

>companies need to replace their switches.

Actually, most Switches are just fine and don't need replacing. IPv6 is a Layer 3 Protocol, most "Normal" Switches operate on Layer 2 (The Ethernet Level, which stays the same and (in the best case) does neither know nor care what goes on in Layers above). These can stay and most wouldn't even need to be reconfigured.

As for Layer 3 Switches (The ones that do some amount of Routing, too), most "brand-name" Models purchased in the last 10 Years should support IPv6.

[ay]

The most hardship, from experience, comes from the apps, especially the home-grown ones.

Let me back this up with an anecdote from experience in dual-stacking the websites at my employer (a curious reader might notice that cisco.com, download.cisco.com, software.cisco.com, tools.cisco.com, cisco-apps.cisco.com are all dualstack. The last one is interesting because it hosts the ordering portal, with IPv6 being a transport for a non-trivial portion of the hardware orders).

While the main cisco.com was dualstack since v6 launch, the rest of the properties required more work, because there's bazillion different apps there, so were launched just a ~year ago.

And yet despite all the testing, once we've gone live post-testing, we realized there was one bug that slipped through. The name of the error quite especially ironic and the bug, while in a somewhat infrequently used portion, was very visible for IPv6-enabled users.

http://www.gossamer-threads.com/lists/nsp/ipv6/47796 for the full externally visible recount of the matter.

Back then the % of IPv6 users which was accessing the erroring function was low enough that we did not roll back the entire set of changes, and just had the fix developed and deployed, and the whole scenario was relatively painless. (Besides for some semi-friendly beat-up during IPv6 workgroup in RIPE meeting, where this error showed vividly since we had an IPV6-only pilot WiFi SSID along with the usual dualstack)

If the same story were to happen with 50% of IPv6 adoption ? That would hurt way way more.

The moral:

If you're a big shop - start auditing your apps now even if you do not think you need it until 3 years from now. If you're not sure - there's bazillion resources and people available to help, but for free and for money.

If you're a small shop and don't have any apps - RTFM, assess, and JustDoIt(tm), in a staged manner, of course, all disclaimers apply, etc. - the sooner you get a (small) chance to make your mistakes while doing the first steps with IPv6, the cheaper those mistakes will be. Of course best to avoid them, but.

Ok, I'm officially off my "IPv6 soapbox" on this thread, hopefully these were useful to some folks. ;-)

[runeks]

> > companies need to replace their switches.

> Actually, most Switches are just fine and don't need replacing. IPv6 is a Layer 3 Protocol, most "Normal" Switches operate on Layer 2 (The Ethernet Level, which stays the same and (in the best case) does neither know nor care what goes on in Layers above).

But these can't do routing, I assume. I think I may have misspoke, and said "switches" when I should have said "routers".

If routers from the last 10 years all support IPv6, that's probably a part of the reason that IPv6 access to Google in the US is 10% IPv6.