Alternative Re: ipv4/25s and above Re: 202211201009.AYC

Tue Nov 22 18:19:34 UTC 2022

John Curran wrote:
>
>> On Nov 22, 2022, at 9:09 AM, John Curran <jcurran at istaff.org> wrote:
>> ...
>> Interoperability isn’t insurmountable, but does take some investment 
>> of effort.  One can imagine any number of techniques (e.g.  flag day 
>> after which “production devices” on the Internet must support 240/4, 
>> or DNS resolver hacks that fail to return “A” records with 240/4 
>> addresses unless a flag is set that says “we’re in the 240/4 routable 
>> Internet” [ick], etc., etc.)  It doesn’t seem particularly hard to 
>> come up with some approaches to solve the interoperability problem, 
>> but completely ignoring it is not an answer (and makes it rather 
>> difficult to take your proposal seriously…)
>
> Joe -
>
> By the way, you shouldn’t feel particularly bad about skipping out on 
> the interoperability requirement – anything involving interworking 
> with the installed Internet is hard, and this is the same lesson that 
> the IPv6 folks found out the hard way…   I will confess that I was a 
> member of the IETF's IPng Directorate and thus inherently complicit in 
> that particular fiasco –

John,

Flags days on the internet of today have proven to be of limited value.

Suppose complete interoperability is never actually solved. Why does 
240/4 utilitarian value have to be binary? I think we should be trying 
to discover these things instead of using them to handwave away any attempt.

The part I feel bad about is that I am actually un-involved in much of 
anyway with the 240/4 or other ideas, my sole input has been to attempt 
to encourage serious consideration and to rebut  naysaying.

Yes, a standards update is only the beginning of a real effort, although 
plenty has changed even without that.

Yes, there may and likely will be a large extent of interoperability and 
usability challenges for quite some time, perhaps even enough time that 
the issue becomes moot.

Yes, it may be insurmountable.

Yes, it may render 240/4 unusable and undesirable to the extent that it 
has little contributory effect on IPv4.

However it may not and discouraging serious consideration is actually a 
contributing factor preventing any such potential.

And to the extent that you and others have discussed and aired various 
points of views and insights, I think I have had some success with my 
efforts thus far.

>
> With IPv6, the first answer to interoperability was “let’s do tunnels 
> between IPng islands”; i.e. helpful for lab environments but useless 
> otherwise.  We then declared that transition was a problem “to be 
> solved later” but that shouldn’t get in the way of the declaration of 
> IPng as the new IPv6.  Finally, after failing to solve the problem, we 
> reverted to “ships in the night”; i.e. IPv4 and IPv6 running in 
> parallel on the same infrastructure – it works, but defeats the entire 
> idea of IPv6 as a functional substitute for IPv4 for connecting new 
> customers and infrastructure to the existing IPv4-based Internet 
> (Luckily, the service provider industry that was growing most rapidly 
> realized that they really needed IPv6, and they really needed 
> transition solutions that allowed IPv6 to interoperate for IPv4 for 
> new connections, and so we eventually saw real solutions such 
> as 464xlat, ds-lite, etc.)

I feel there is some value for the internet record to contain as much as 
possible real debate and consideration instead of group think, 
short-sightedness, idealouges and top down approaches which may not look 
pretty in hindsight. Such as contained in the much larger details of 
your brief recap and that you and others have expanded upon here and 
elsewhere in the past.

In other words, a loyal opposition.

>
> Maintaining interoperability with the existing base is hard - far 
> harder than just “updating the standard” -
Without a standard update, there is a bit of a chicken and egg problem 
with pursuing interoperability with any seriousness.

I think 100.64/10 was a missed opportunity to incentivize the industry 
to pursue interoperability.

> but is absolutely essential if you want viable reuse of 240/4.  Of 
> course, it does raise the question of whether the total effort will be 
> worth the purported gain, but that really can’t be assessed until 
> there's some specification of the proposed solution for 
> interoperability with the existing deployed devices that don’t know 
> about the 240/4 change.
>
> Thanks,
> /John
>
> p.s.  Disclaimer(s): my views alone. Warning: may cause dizziness, 
> headaches, or nausea.
>
Best,

Joe