IPv6 Ignorance

John Mitchell mitch at illuminati.org
Mon Sep 17 12:28:09 UTC 2012


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.

There's a great article on the myths and debunks of the address space at 
http://rednectar.net/2012/05/24/just-how-many-ipv6-addresses-are-there-really/ 
one of the things it talks about is the /64 and /48 allocation.

<snip>
 > Given that the first 3 bits of a public IPv6 address are always 001, 
giving /48 allocations to customers means that service providers will 
only have 2^(48-3) or 2^45 allocations of /48 to hand out > to a 
population of approximately 6 billion people. 2^33 is over 8 billion, so 
assuming a population of 2^33, there will be enough IPv6 /48 allocations 
to cater for 2^(45-33) or 2^12 or 4096 IPv6 > address allocations per 
user in the world."
</snip>

- Mitch -


On 17/09/12 04:23, Randy Bush wrote:
> [ yes, there are a lot of idiots out there.  this is not new.  but ]
>
>> "We are totally convinced that the factors that made IPv4 run out of
>> addresses will remanifest themselves once again and likely sooner than
>> a lot of us might expect given the "Reccomendations" for "Best
>> Practice" deployment."
> while i am not "totally convinced," i am certainly concerned.  we are
> doing many of the same things all over again.  remember when rip forced
> a homogenous, often classful, mask length in a network and we chewed
> through /24s?  think /64 in ipv6, except it's half the bits not 1/4 of
> them.  remember when we gave out As and Bs willy nilly?  look at the
> giant swaths of v6 we give out today in the hopes that someone will
> deploy it.
>
> and don't bs me with how humongous the v6 address space is.  we once
> though 32 bits was humongous.
>
> randy




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