Re: [IPv6] Second Working Group Last Call for <draft-ietf-6man-rfc6724-update>

[Kyle Rose <[e-mail]>]

Globally publishing addresses that are unreachable means clients will try
to connect to addresses that are known a priori to the address publisher to
be unreachable from much of its audience. Anyone who cares about
performance will not want to take the hit of clients waiting for a timeout,
if the application even implements retries.

Happy Eyeballs is a mitigation for configuration errors and transient
connectivity problems: it's not part of the TCP handshake for a reason, and
should not be required for a properly-configured client on a
properly-configured and fully-working network to reach a
properly-configured service.
Kyle

On Thu, Apr 11, 2024 at 8:02 AM Ted Lemon <[e-mail]> wrote:

> Perhaps we could start by having you explain why it's a bad practice,
> Kyle, since this does not appear to be universally accepted as true? :)
>
> On Thu, Apr 11, 2024 at 7:53 AM Kyle Rose <[e-mail]> wrote:
>
>> Also, MUST allows us to make ULA more useful than it is today. It is
>>> *desirable* to be able to publish non-local ULAs and have hosts know what
>>> is local and what is not. As a simple example: once all hosts implement the
>>> MUST, it will be safe to publish local ULAs in the global DNS, because
>>> hosts won't try to use them unless they are local.
>>>
>>
>> Perhaps ironically, this is the best argument I've read in opposition to
>> mandating the policy table be updated for known-local ULAs. Unreachable
>> addresses should never be published in global DNS with the intent that
>> clients figure it out, and the IETF should publish a standards track
>> document explaining why this is a bad practice.
>> Kyle
>>
>>