Where to buy Internet IP addresses

Joe Greco jgreco at ns.sol.net
Mon May 4 17:09:04 CDT 2009


> On Mon, 04 May 2009 17:03:31 -0400, Bill Stewart <nonobvious at gmail.com>  
> wrote:
> > When I came back, I found this ugly EUI-64 thing instead,
> > so not only was autoconfiguration much uglier,
> > but you needed a /56 instead of a /64 if you were going to subnet.
> > Does anybody know why anybody thought it was a good idea
> > to put the extra bits in the middle, or for IPv6 to adopt them?
> 
> "64bit MAC" -- which pretty much exists nowhere.  It's a repeat of the  
> mistakes from IPv4's early days: CLASSFUL ROUTING.

Actually, that's exactly wrong.

It takes the good stuff from one of the failures of IPv4... CLASSFUL
ROUTING...  and does it right:

Fundamentally, IPv4 got one part of it right with classful routing.
Giving service providers large blocks of space, large enough to allow
them to announce a single route out on the Internet.  The problem is
that the address space wasn't really large enough to support this in
a sane manner, because growth wasn't predictable and mistakes would
result in waste.

IPv6 is *designed* for waste.  You are *expected* to have vast realms
of completely unused IP(v6) addresses.  So there is no damage to be had
by giving someone a delegation that's an order of magnitude too large,
and even giving someone a delegation that's an order of magnitude too
small is survivable without real problems.  We can also delegate based
on much more distant projections.

Reducing the routing table size is one of the BEST ideas from classful
routing, it just didn't pan out because it was done as classful routing.

Now, we get a chance to learn from that mistake, and we can do it right.

Using a 64-bit MAC when most current MAC's are 48 is not a mistake.  It
shows that someone somewhere had some vision towards the future.

> I'm with you.  I wish vendors and spec designers would just get over it  
> and let people subnet however they want.  If I want to set a network to be  
> /96 or /120, I should be allowed to do so.  Yes, I know autoconfig will  
> not work -- and I don't want it to.

You *can* do that.  Nobody has said that it is impossible to set up an
interface with a /130-slash-/131 if you want a point to point. 

But what we're talking about is service providers delegating to customers.
Customers should *also* be allowed to subnet "however they want." 
Something they can't do right now, because they aren't given the space. 
If service providers are allowed to delegate teeny prefixes (meaning /64
or less), we're going to see consumers finding "ways" around that 
restriction, and then we're down an ugly road that's reminiscent of IPv4 
and NAT and "you get one IP address, deal with it."

That should be avoided at all costs.

... JG
-- 
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.




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