Re: [Anima] I-D Action: draft-ietf-anima-autonomic-control-plane-08.txt

[Michael Richardson <[e-mail]>]

Brian E Carpenter <[e-mail]> wrote:
    > I get a bit confused by the way your mail agent doesn't distinguish
    > new and old text, but in line...

Well, there isn't any old text in it, rather there are quotes from the document!

    brian> Toerless explained elsewhere why he thinks the duplication is
    brian> needed.

I read that after my email.
I simply can't agree.

    >> ====== section 11
    >> This document may be considered to be updating the IPv6 addressing
    >> architecture ([RFC4291]) and/or the Unique Local IPv6 Unicast
    >> addresses ([RFC4193]) depending on how strict specific statements in
    >>
    >> I don't like this statement.  Either it violates the spec, and updates it, or
    >> it does not.  I do not think that it violates.  This is not a multi-link
    >> subnet, this is a prefix that is not on-link.

    brian> As readers of the 6man list know, this has been a very contentious topic.
    brian> I think it's safer to duck it in the ACP draft: say what we do, but say
    brian> nothing about RFC4291 etc.

I agree.

    >> It is possible, that this scheme constitutes an update to RFC4191
    >> because the same 64 bit subnet prefix is used across many ACP
    >> devices.  The ACP Zone addressing Sub-Scheme is very similar to the
    >> common operational practices of assigning /128 loopback addresses to
    >> network devices from the same /48 or /64 subnet prefix.
    >>
    >> It does not. Brian? Do you concur?

    > Put it this way. The ACP doesn't assign ULAs using DHCPv6. It doesn't assign
    > them using SLAAC. It doesn't use conventionally sized /64 subnets. So in that
    > sense it is like RFC 6164 ("Using 127-Bit IPv6 Prefixes on Inter-Router Links").
    > But we don't need to apologise. As you say, we're simply assigning /128
    > addresses to (virtual) interfaces using our own scheme. And we're relying
    > on BCP 198 (RFC 7608) which says that routing prefixes can be any length
    > up to /128. If you want to cite anything, cite RFC 7608.

Toerless, do you want text to say this?

    draft> The goal for the 8 or 16-bit addresses available to an ACP device in
    draft> this scheme is to assign them as required to software components,
    draft> which in autonomic networking are called ASA (Autonomic Service

    mcr> We are not providing 8-bit or 16-bit IIDs.
    mcr> We are providing 256 or 65536 /128 addresses which are conveniently
    mcr> aggregated for routing purposes.

    draft> In practical terms, the ACP should be enabled to create from its /8
    draft> or /16 prefix one or more device internal virtual subnets and to
    draft> start software components connected to those virtual subnets.

    mcr> No, don't say this, and don't do this in practice.  Create /128 routes to LL
    mcr> address of the internal VM and configure the /128 as a loopback address
    mcr> inside the VM.

    brian> So yes, I concur with Michael.



--
Michael Richardson <[e-mail]>, Sandelman Software Works
 -= IPv6 IoT consulting =-