[v6ops] Re: Dynamic addresses

[David Farmer <[e-mail]>]

On Wed, Aug 14, 2024 at 04:53 Daryll Swer <contact=
[e-mail]> wrote:

> Gert Doering
>
> There some good arguments for dynamic prefixes
>>
> No there isn't.
>

All addresses are dynamic; they will change. It is a question of over what
period and of whom or what triggers that change. Or, looking at it from
another angle, addresses are never permanent; they will eventually change.

people should stop putting explicit IPv6 addresses into places (which will
>> inevitably cause headaches when changing ISP)
>
> NPTv6 to the rescue for non-renumbering across static ISP PDs that changes
> when ISP *itself* is changed (rather than prefix within the same ISP).
> I'm pretty confident people do not change ISPs per 6 hours or per 24 hours
> etc, as is the case with the lease time on the dynamic prefixes to begin
> with.
>

Yes, reasonable periods of stability are necessary for both addresses and
prefixes. All changes should be coordinated with the users or scheduled to
occur when they cause as little disruption as possible.

So actually having better support for automatic DNS registration/discovery
>> (mDNS and friends) and just making SoHo networks renumber automatically and
>> properly is a worthwile goal.
>
>
> Not sure what you mean, mDNS and friends, does not care about changing GUA
> or ULA prefixes, it operates on link-local addressing and does not work
> inter-VLAN anyway (without hacking using mDNS Repeaters/Proxies because
> link-local) — maybe I missed something here.
>

mDNS provides more than just the link-local addresses. Various DNS-SD
proxies enable mDNS to operate beyond a single link.

I do agree that those 0.001% of people that SSH into their home
>> servers will hate SSHs dying on a renumbering event
>
>
> Are you a gamer, Gert? Because many end-users are (myself included), and
> if the games they play use IPv6 and works P2P native (we intend to have
> IPv6 for every layer 7 application, I hope), RIP (literally) to the player,
> when the genius ISPs flip the prefix on a live-session — same impact as the
> SSH example.
>
> Do we really need to create a list of everyday applications (beyond the so
> called 0.001% SSH users) that'd be impacted by dynamic/ever-changing 24/7
> prefixes? I'm sure you got the point.
>

Again, addresses and prefixes are not permanent; they inevitably change for
one reason or another. They should not be changed haphazardly or too
frequently, and these modifications should occur smoothly, aiming to
minimize disruption, usually with some overlap between the old and new
addresses or prefixes.

However, the idea that addresses should not change is IPv4-centric
thinking. IPv6 was architected with the idea that addresses are meant to be
changed with minimal disruption. What is unacceptable is ISPs deliberately
disrupting addresses or prefixes to differentiate service tiers; paying
someone to prevent a disruption intentionally caused by them is considered
extortion.

Thanks