[c-nsp] IPv6

TJ trejrco at gmail.com
Tue Mar 16 19:52:08 EDT 2010


I tried holding back ... and failed.


> -----Original Message-----
> From: cisco-nsp-bounces at puck.nether.net [mailto:cisco-nsp-
> bounces at puck.nether.net] On Behalf Of Ziv Leyes
> Sent: Tuesday, March 16, 2010 11:19
> To: cisco-nsp at puck.nether.net
> Subject: Re: [c-nsp] IPv6
> 
> Many people nowadays believe we can start wasting the IPv6 address space
> because they all claim it's so astronomically large that we shouldn't
worry
> about depletion as it happened with IPv4

/64s are not about waste, or address efficiency.  It is about efficiency in
delivering services ... scaling ... 


> And I'd like to set an appointment with all of them in let's say 20/30
> years from now and talk about it again.

To loosely quote Vint Cerf, 32 bits was meant to be a test run / proof of
concept - wasn't supposed to become The Real Deal.


> If you could go back in time and ask the guys that planned the IPv4 why
> didn't they do it larger they would tell you there is no way we'll ever
> need more than that, right?

While they almost certainly couldn't have expected what the Internet has
become, to say they didn't appreciate the need for address space is folly.


> We're now facing the same situation, we can't even imagine what can happen
> in 20 years from now, as I'm already hearing about giving every milk
> cartoon a /64 which won't be recycled.

A milk cartoon would not get a /64.  It wouldn't get an address at all
unless it is network connected.  
Long before we need to worry about IPv6 address exhaustion we'll need to
fret about MAC addresses being used up.
(These types of statements are a pet peeve of mine - addresses are only
really addresses when connected to a network, or intended to be so
connected.  Otherwise they are not addresses so much as another form of
unique ID.  If you REALLY, REALLY wanted to give them all an address it
would be a /128 - so let me know when you have used up one /64
(~18BillionBillion) ... and then we'll talk.


> Think about it, how many milk cartoon we dispose daily? How many IP
> addresses are in a /64? Now start making the math and you'll see that the
> astronomic and virtually endless range starts to slowly shrink...
> But hey, I'm used to be the "crazy guy" that alerts about nothing and then
> a few years later say "I told you..."

That's the thing - it doesn't, not really.  It is simply a LOT of addresses
... and, in the VERY RARE care that we find that 2000::/3 was just burned
through (a problem some of us would welcome!), we can reconsider for
4000::/3, or 6000::/3, or 8000::/3, or A000::/3, or C000::/3 ... (note: I am
not arguing for inefficiency, just a different model of efficiency).


> So who's up for it? Let's talk about it in 20 years from now?
> BTW, I will be more than happy to be wrong!

Yes, let's!  I'll buy you a drink and we can commiserate about how easy the
next generation has it, what with all of those IPv6 gadgets just working and
making life so easy they don't even think about "the network" anymore ;).


/TJ



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