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What to Wear on World IPv6 Day

This Wednesday, June 8, is World IPv6 Day. What happens on a day with that weighty a milestone? Testing, testing and more testing.

By now, this should be ringing some bells. Sometime between Halloween and the next New Year, the set of Internet-protocol addresses under the current numbering system, IPv4, will vanish. Kaput. No more.

In its place will be IPv6 addresses. That’s important because of the increasing number of things in our daily lives that work best (or only) when connected to the Internet. Anything that hooks up to the Internet gets an IP address: computers, laptops, smartphones, connected TVs, tablets.

The great thing about IPv6 addresses is that there will apparently always be enough to go around, no matter how Internet-crazy and cloud-addicted we get. Its breadth is the layman’s equivalent of “gazillions.”

Lately, though, I’ve been wondering about what happens when something goes wrong. What happens in that IPv4-heavy household, when there’s no more IPv4? Does the Internet seem slower? Do certain apps lock up? Blue screen of death?

In wholly unscientific hallway discussions with people who work on this transition for a living, it appears that more than half of home routers (the thing after the cable modem that sprays signal around for all your stuff) are IPv4. Many of the “connected TVs,” so splashy just six months ago at CES, aren’t IPv6.

Turns out that the question of what happens has different answers. As with most other complex technological marathons, it depends. (Sorry! Sorry!)

Most, if not all, of the major cable providers are transitioning to IPv6 in a way that should earn them the right to say, “We got ya covered.” IPv4, IPv6, sure. Either. If they do their thing right, you’ll keep doing your things right, no issues.

Always in these conversations, though, one tech term emerges, spoken ominously: carrier-grade NAT, where NAT stands for Network Address Translation. Boiled way down, it goes like this: Share the limited number of IPv4 addresses among everyone who needs them.

Surprise: It’s starting to look like certain applications won’t do well in a carrier-grade NAT environment. Think of any app that needs to talk a lot, back and forth with the “cloud.” Streaming video comes to mind, and over-the-top voice, and peer-topeer file-sharing.

Which brings us back to World IPv6 Day. What goes wrong will hopefully get a lot more informed - because forearmed is forewarned.

As for what to wear: Geek out, brothers and sisters. And if you’re aching for more, don’t forget the IPv6 Summit at next week’s Cable Show in Chicago, on Tuesday, June 14. Maybe I’ll see you there.

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