v6 subnet size for DSL & leased line customers

Joe Greco jgreco at ns.sol.net
Mon Dec 24 01:27:55 UTC 2007

> > > I think Ethernet is also another example of the benefits of
> > > spending/"wasting" address space on operational convenience - who needs
> > > 46/47 bits for unicast addressing on a single layer 2 network!? If I
> > > recall correctly from bits and pieces I've read about early Ethernet,
> > > the very first versions of Ethernet only had 16 bit node addressing.
> > > They then decided to spend/"waste" bits on addressing to get
> > > operational convenience - "plug and play" layer 2 networking.
> > 
> > The difference is that it doesn't "cost" anything.  There are no RIR fees,
> > there is no justification.  You don't pay for, or have to justify, your 
> > Ethernet MAC addresses.
> > 
> > With IPv6, there are certain pressures being placed on ISP's not to be
> > completely wasteful.
> I don't think there is that difference at all. MAC address allocations
> are paid for by the Ethernet chipset/card vendor, and I'm pretty sure
> they have to justify their usage before they're allowed to buy another
> block. I understand they're US$1250 an OUI, so something must have
> happened to prevent somebody buying them all up to hoard them, creating
> artificial scarcity, and then charging a market sensitive price for
> them, rather than the flat rate they cost now. That's not really any
> different to an ISP paying RIR fees, and then indirectly passing those
> costs onto their customers.

MAC address allocations are paid for by the Ethernet chipset/card vendor.

They're not paid for by an ISP, or by any other Ethernet end-user, except
as a pass-through, and therefore it's considered a fixed cost.  There are
no RIR fees, and there is no justification.  You buy a gizmo with this
RJ45 and you get a unique MAC.  This is simple and straightforward.  If
you buy one device, you get one MAC.  If you buy a hundred devices, you
get one hundred MAC's.  Not 101, not 99.  This wouldn't seem to map well
at all onto the IPv6 situation we're discussing.

With an IPv6 prefix, it is all about the prefix size.  Since a larger 
allocation may cost an ISP more than a smaller allocation, an ISP may 
decide that they need to charge a customer who is allocated a /48 more 
than a customer who is allocated a /64.

I don't pay anyone anything for the use of the MAC address I got on this
free ethernet card someone gave me, yet it is clearly and unambiguously
mine (and only mine) to use.  Does that clarify things a bit?

If you are proposing that RIR's cease the practice of charging different
amounts for different allocation sizes, please feel free to shepherd that
through the approvals process, and then I will certainly agree that there
is no longer a meaningful cost differential for the purposes of this
discussion.  Otherwise, let's not pretend that they're the same thing, 
since they're clearly not.

... 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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