[ih] IETF relevance (was Memories of Flag Day?)

[Brian E Carpenter]

On 11-Aug-23 09:14, John Levine via Internet-history wrote:
...

> In retrospect it was a big mistake not to have a migration path from
> IPv4 to IPv6, 

What do you mean? There's always been a migration path. It has
been immensely complicated by the market success of NAT44, but
we knew from Day 1 that we needed both coexistence and a
transition plan. In fact, we knew it before IPv6 was picked
as the design (RFC1671).

> and the IPv6 crowd did themselves no favors by insisting
> for years that it was perfect and it didn't need DHCP and a bunch of
> other stuff that it now finally has. 

Well, DHCPv6 was standardised by 2003, before IPv6 deployment
really got serious. DHCP(v4) was standardised in 1993, but at the
time of IPv6 basic design it was neither proven nor widespread,
so IPv6 took its cue for automatic configuration from various
successful proprietary protocols.

On 11-Aug-23 04:16, Jack Haverty via Internet-history wrote:
...

> Instead we now live with a multi-protocol Internet, and the complexity 
> and problems that come with it.

That's true, but I'm afraid it was historically inevitable.
The need for IPv6 was identified around the same time that the
start of the Web and the invention of NAT44 (or more precisely
NAPT44) led to the .com boom. That boom made a rapid transition
of the network layer impossible - i.e., not only was no flag
day conceivable, but also a consensual managed transition became
completely impracticable.

On the good news front, I hear that traffic on the WLCG (the
Worldwide Large Hadron Collider Computing Grid) is now
"regularly more than 90-95% using IPv6". They have essentially
completed a managed transition.

If you want to dig into the details, several people have
contributed to this writeup:
https://github.com/becarpenter/book6/blob/main/3.%20Coexistence%20with%20Legacy%20IPv4/3.%20Coexistence%20with%20Legacy%20IPv4.md

    Brian