Re: [v6ops] Thoughts about wider operational input

[Ted Lemon <[e-mail]>]

Oh, now that's really interesting. I'm glad I asked the clarifying
question. So when you have a host with a ULA, it doesn't try to do NAT64 I
guess because it thinks it needs a GUA to do that?

On Tue, Mar 22, 2022 at 9:35 PM Nick Buraglio <[e-mail]> wrote:

> Yes, I know I have harped on this many times and have posted some
> simple examples of the behavior to the list. My experience has been, and
> continues to be, that if I have dual stacked hosts with A and AAAA records,
> and the IPv6 clients are using ULA that IPv6 is never used. In an IPv6-only
> environment ULA has no higher priority protocol to supersede the ULA. In
> the context of transitioning to an IPv6 world, it is fairly unrealistic to
> assume any kind of greenfield, and dual-stack is by and large the standard
> "permanently temporary" solution for the vast majority of implementations.
> So in this context, which has been 99% of what I have seen until I began
> working on the IPv6-only implementation mandated by the USG OMB-M-21-07
> document, that was the de facto standard (and will continue to be for
> enterprise deployments, in my opinion).
> I would be happy to be incorrect about this, honestly it would make my
> work-life easier if I was. So, yes, I fully acknowledge that your use case
> is absolutely the right one for ULA. For doing a transition in an existing
> network (which circles back the the original topic of this thread: getting
> enterprises to use IPv6 in a meaningful way), this is a really well put
> together descriptions of the every-day implications of trying to use ULA:
> https://blogs.infoblox.com/ipv6-coe/ula-is-broken-in-dual-stack-networks/
>
> nb
>
>
>
>
>
> On Tue, Mar 22, 2022 at 3:20 PM Ted Lemon <[e-mail]> wrote:
>
>> I'm sure you believe this assertion, Nick, but you haven't given us any
>> way of understanding why you believe this. In fact we're using ULAs in the
>> Thread Border Router to enable IPv6 communication between different
>> subnets, which literally could not be done with IPv4. So at least for this
>> use case, ULAs work well. Would it work better to have a GUA? Comme ci
>> comme ça. On the one hand, prefix delegation and real routing would make
>> the solution more general. On the other, GUAs are great for reaching out to
>> the internet, which we may or may not want light bulbs to be able to do.
>>
>> On Tue, Mar 22, 2022 at 9:13 PM Nick Buraglio <[e-mail]> wrote:
>>
>>> ULA is an operational non-starter in the presence of any dual stacked
>>> hosts.  Per its design, it just won't ever use IPv6 in any meaningful way
>>> and that time and effort are better served on adding GUA addressing of one
>>> kind or another.
>>>
>>> nb
>>>
>>>
>>>
>>> On Tue, Mar 22, 2022 at 2:55 PM Brian E Carpenter <
>>> [e-mail]> wrote:
>>>
>>>> Hi Gert,
>>>>
>>>> I see that the discussion has been going on while I was sleeping, but I
>>>> want to clarify below...
>>>> On 22-Mar-22 21:30, Gert Doering wrote:
>>>> > Hi,
>>>> >
>>>> > On Tue, Mar 22, 2022 at 11:42:12AM +1300, Brian E Carpenter wrote:
>>>> >> I agree with Jordi that multihoming is a genuine impediment. What
>>>> isn't generally realised is that it's a problem of scale when considering
>>>> at least 10,000,000 enterprises, much more than it's a problem of IPv6
>>>> itself.
>>>> >
>>>> > What is "an enterprise"?
>>>> >
>>>> > My stance on this is that for "largely unmanaged SoHo networks" -
>>>> which
>>>> > could be called "small enterprise" - dual-enduser-ISP with dual-/48 or
>>>> > NPT66 gets the job done in an easy and scalable way (HNCP would have
>>>> > been great, but IETF politics killed it).
>>>> >
>>>> > "Enterprise that truly need their own independent fully managed
>>>> network
>>>> > with multiple ISP uplinks and fully routed independent address space"
>>>> > are probably way less than 10 million...
>>>>
>>>> I came up with 10 million quite some years ago as a reasonable estimate
>>>> of the number of medium to large businesses in the world, all of which
>>>> might depend on *reliable* Internet access to survive (and WfH during
>>>> COVID has made this even more important recently). So all of them
>>>> should have two independent paths to the Internet to assure reliability.
>>>> That means two different ISPs (or less good, two completely independent
>>>> paths to the same ISP).
>>>>
>>>> So, if PI addressing is the answer, that really does take us to
>>>> 10M /48s to be routed.
>>>>
>>>> If PA is the answer, that's why I worked on SHIM6 (may it rest in
>>>> peace). Which is why I worked on RFC 8028. If that's not the
>>>> answer, we're back to NPTv6. Possibly even to ULA+NPTv6.
>>>>
>>>> > Half of them do not want Internet access anyway, just access to their
>>>> > ALGs that will do the filtering and TLS inspection and everything, and
>>>> > then out to the Internet as a new TCP session (= could be done with
>>>> > DMZ islands of upstream-provider-allocated space just fine).
>>>> >
>>>> >
>>>> > We need to work on our marketing regarding multihoming.  "What is it
>>>> that
>>>> > you get, what is the cost, which of the variants do you want, and
>>>> why...?"
>>>>
>>>> Yes.
>>>>     Brian
>>>>
>>>> _______________________________________________
>>>> v6ops mailing list
>>>> [e-mail]
>>>> https://www.ietf.org/mailman/listinfo/v6ops
>>>>
>>> _______________________________________________
>>> v6ops mailing list
>>> [e-mail]
>>> https://www.ietf.org/mailman/listinfo/v6ops
>>>
>>