IPv6 Ignorance

Mon Sep 17 18:27:04 UTC 2012

On Sep 17, 2012, at 08:18 , Matthew Kaufman <matthew at matthew.at> wrote:

> On 9/17/2012 5:28 AM, John Mitchell wrote:
>> I think people forget how humongous the v6 space is...
>> 
>> Remember that the address space is 2^128 (or 340,282,366,920,938,463,463,374,607,431,768,211,456 addresses) to put the in perspective (and a great sample that explained to me how large it was, you will still get 667 quadrillion address per square millimetre of the Earth’s Surface.
> 
> Yes. But figure an average subnet has, what, maybe 5 hosts on it? (Sure, there's some bigger ones, but a whole lot of "my router, my PC, and maybe my printer" networks too.
> 
> So even if you could use all the top bits (which you can't, as many combinations are reserved), that's more like 92,233,720,368,547,758,080. And if you lop off the top three bits and just count the space currently assigned to Global Unicast, that's 11,529,215,046,068,469,760. Which is 0.02 per square mm of the earth's surface. Or just over 2 per square centimeter.
> 
> Powers of two get big fast... but they get small fast too.
> 
> Matthew Kaufman

What technology are you planning to deploy that will consume more than 2 addresses per square cm?

Owen