v6 subnet size for DSL & leased line customers

Mark Smith nanog at 85d5b20a518b8f6864949bd940457dc124746ddc.nosense.org
Mon Dec 24 04:56:19 UTC 2007

On Sun, 23 Dec 2007 19:27:55 -0600 (CST)
Joe Greco <jgreco at ns.sol.net> wrote:

> > > > 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.

How many ISP customers pay RIR fees? Near enough to none, if not none.
I never have when I've been an ISP customer. Why are you pretending
they do? I think your taking an end-user perspective when discussing
ethernet but an RIR fee paying ISP position when discussing IPv6 subnet
allocations. That's not a valid argument, because you've changed your viewpoint on the situation to suit your position.

Anyway, the point I was purely making was that if you can afford to
spend the bits, because you have them (as you do in Ethernet by design,
as you do in IPv6 by design, but as you *don't* in IPv4 by design), you
can spend them on operational convenience for both the RIR paying
entity *and* the end-user/customer. Unnecessary complexity is
*unnecessary*, and your customers won't like paying for it if they
discover you've chosen to create it either on purpose or through

> 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.


        "Sheep are slow and tasty, and therefore must remain constantly
                                   - Bruce Schneier, "Beyond Fear"

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