A crazy idea

Joe Maimon jmaimon at jmaimon.com
Mon Aug 2 21:52:17 UTC 2021

Owen DeLong wrote:
>> On Jul 29, 2021, at 14:06 , Joe Maimon <jmaimon at jmaimon.com> wrote:
>> tim at pelican.org wrote:
>>> On Monday, 19 July, 2021 14:04, "Stephen Satchell" <list at satchell.net> said:
>>>> The allocation of IPv6 space with prefixes shorter than /64 is indeed a
>>>> consideration for bigger administrative domains like country
>>>> governments, but on the other end, SOHO customers would be happy with
>>>> /96, /104 or even /112 allocations if they could get them.  (Just how
>>>> many light bulbs, fridges, toasters, doorbells, phones, &c does SOHOs
>>>> have?)  I would *not* like to see "us" make the same mistake with IPv6
>>>> that was made with IPv4, handing out large blocks of space like so many
>>>> pieces of M&M or Skittles candy.
>>> Nay, nay, and thrice nay.  Don't think in terms of addresses for IPv6, think in terms of subnets.  I can't stress this enough, it's the big v4 to v6 paradigm shift - don't think about "how many hosts on this net", think about "how many nets".
>> Think of how many large ISP's a /3 of ipv6 effectively holds, assuming that /48 per customer is the norm, and /24 up to /12 assignments for those ISP's is also.
>> In those terms IPv6 isnt that much bigger.
> Let’s say an average “large” ISP burns a /11 of IPv4 serving their ~2M customers with a single IPv4 address each.
> IPv4 supports a maximum of 2,048 such ISPs without regard to space for multicast, class E, etc. (which reduce this number).
> Let’s say that we give each of them enough space to issue 16M /48s (an IPv6 /24).
> That means we have 2^21 IPv6 large ISPs serving 8x as many customers with /48s.
> That’s 2 million large ISPs covered in the first /3.
> Since each of them is serving around 2M customers, that’s 4,000,000,000,000 customers.
> For comparison, the world population is less than                8,000,000,000.
> Tell me again how IPv6 is not that much larger, Joe?
> Owen

I will simply point out that even by this measurement, we have reduced 
IPv6 scarcity-free longevity from mind boggingly larger into only a 2-3 
thousand times larger. Thats enough of an accomplishment that I dont 
even have to delve into the discussions and proposals, some you were 
even a part of that could have resulted in even larger allocations to 
mega ISP's being acceptable, and still might.

Continuing to operate under the belief that there isnt any way we can 
use ipv6 that can result in some form of scarcity may very well cause 
that scarcity to become a serious possibility much sooner than might 
have ever been expected, with much larger and entrenched consequences 
than we can predict today.

So lets stop saying IPv6 is infinite. We can cede enough bits to cause 
scarcity to an upcoming generation who wont thank us.

I propose that any way we decide to use IPv6 today we should be able to 
say confidently will continue to operate under any imaginable scenarios 
for the next century, minimally.

Thats a conservative number considering that it would have been nice had 
they done a quarter of that for IPv4 back when it was where ipv6 is now.


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