IPv4 Residual Deployment via IPv6 - A Stateless Solution (4rd)
draft-ietf-softwire-4rd-10

[Ballot comment]
I'm adding this comment in response to some of the comments raised by Adrian and concurred with by several other ADs.  If it had been my personal choice, I would have proposed either publishing this document as Informational, or through the ISE.  However, the working group consensus was to publish this document as an Experimental document.  I would need a strong reason to push back on the working group consensus, and the best I could come up with is that it would somehow look better.  The allocation of an RFC number would not change, and the document would still get published.  So I see no point in going down that path.

As to the experimental status of the document, and "protecting the internet" from it, on the one hand the experimental status of the document does legitimately lead us to want to ask that question, but on the other hand I think the answer to that question is that there is no risk to the internet from this specification.  Like any A+P solution, it will be expensive to deploy, and will not be deployed broadly across the Internet in a way that requires end-to-end interoperation.

So the goal when considering interoperability and harm to the internet with this document should be "what harm will come if a host that is reachable over this technology attempts to connect to some arbitrary host on the internet that may or may not be using this technology (or some other A+P technology)."  The working group considered this technology at length and identified no such issues other than those currently documented, to which Adrian and the others have not raised specific objections.  This technology was a candidate for being chosen as the working group's proposed solution to the lightweight CGN problem.  It wasn't selected, but would have been a viable candidate.

Consequently, I conclude that no actionable point has been raised here.  I think it is unreasonable to ask the authors or the working group to attempt to come up with some pro forma list of issues from which the Internet need be protected when there are currently no such known issues, and when there is no stated reason to think that such issues exist or need to be addressed.

Were I to advise a working group on how to approach such a decision in the future, I would advise them not to follow the path that the working group followed in this case.  However, that is water under the bridge.  I therefore consider this particular issue to be closed.

[Ballot comment]
I discussed my Discuss with the responsible AD, and arrived at an understanding that the text in RFC 3315 for the registry is not as clear as it could have been.

Our agreement is that the allocation policy is meant to be:
Either
  Standards Action
Or
  Expert Review with guidance to the DE including that the
  allocation can be reclaimed if it turns out that the use of
  the codepoint is not successfully deployed.

This is obviously not what 3315 actually says, but I have cleared my Discuss on the understanding that some effort will be made to document this allocation policy, and an attempt will be made to get IETF consensus on this.

===

Just like draft-ietf-softwire-map-t, I don't specifically care to
object to the publication of this document and I don't feel strongly
enough to abstain, but I do find it hard to understand why it is being
published even as experimental. It feels to me like a consolation prize
for not being the WG's selected solution. Maybe it would have been
better to pursue publication either as an historic record of an idea
not adopted, or as an informational record of some existing
implementation and deployment. That way it would have been less
confusing to the market.

Anyway, given that it is positioned as an experimental RFC, I wish this
document explained why and how it is experimental in nature. It is not a
requirement to do this, but it would make a lot of sense.

- How is the Internet kept safe from the experiment?
- What feedback do you want from experimentation?
- How will you judge the success of the experiment?
- How do you plan to move the experiment to standards track?

[Ballot comment]
Exactly like Adrian, I would like some more information on the Experimental
status. As examples:
  http://tools.ietf.org/html/rfc7360#section-1.3
  http://tools.ietf.org/html/rfc6614#section-1.3

I believe this should be common practice for experiemental RFCs.
Re-reading RFC 3933, and I don't see this.
Maybe an IESG statement ... ?

[Ballot comment]
I don't see a lot of positive outcomes from advancing additional transition mechanisms I find myself altogether better off when I can avoid using any of them.

[Ballot comment]
I'm with Brian and Adrian on this draft: It is not clear to me why the softwire WG  is publishing this document. It could have been submitted via the ISE, if there is the desire to document the existence of a different approach.

[Ballot discuss]
I could not parse the IANA considerations section of this document.

  IANA is requested to allocate the following:

  o  One DHCPv6 option codes TBD1 for OPTION_4RD of Section 4.9
      respectively (to be added to section 24.3 of [RFC3315].
      Encapsulated options of OPTION_4RD, 4RD_MAP_RULE (TBD2) and
      4RD_NON_MAP_RULE (TBD3) should also be recorded into the DHCPv6
      option code space.

        Value  |    Description  |  Reference
      -----------+------------------+---------------
          TBD1  |    OPTION_4RD    | this document
          TBD2  |  4RD_MAP_RULE  | this document
          TBD3  | 4RD_NON_MAP_RULE | this document

I think it is just jumbled words. You are asking for three new DHCPv6
option codes from the "Dynamic Host Configuration Protocol for IPv6
(DHCPv6)" registry "Option Codes" sub-registry.

Now, that sub-registry is marked "Expert Review and Standards Action"
which is slightly ambiguous.  So I went to RFC 3315 where I found...

  New DHCP option codes are tentatively assigned after the
  specification for the associated option, published as an Internet
  Draft, has received expert review by a designated expert [11].  The
  final assignment of DHCP option codes is through Standards Action, as
  defined in RFC 2434 [11].

So, you can't have code points for an Experimental RFC.

Rather than move this document to the Standards Track, I suggest you
take advantage of draft-ietf-softwire-map-dhcp which is on the Standards
Track and is already in the pipe.  If you update that document to ask
for these code points, and include a normative reference to this I-D
everything should work out fine.

[Ballot comment]
Just like draft-ietf-softwire-map-t, I don't specifically care to
object to the publication of this document and I don't feel strongly
enough to abstain, but I do find it hard to understand why it is being
published even as experimental. It feels to me like a consolation prize
for not being the WG's selected solution. Maybe it would have been
better to pursue publication either as an historic record of an idea
not adopted, or as an informational record of some existing
implementation and deployment. That way it would have been less
confusing to the market.

Anyway, given that it is positioned as an experimental RFC, I wish this
document explained why and how it is experimental in nature. It is not a
requirement to do this, but it would make a lot of sense.

- How is the Internet kept safe from the experiment?
- What feedback do you want from experimentation?
- How will you judge the success of the experiment?
- How do you plan to move the experiment to standards track?

[Ballot discuss]
Could you please work through the suggestions made in the SecDir review on the SecDir list with Derek, I don't see a response on list yet.  I agree with Derek that the first section in the security considerations section on anti-spoofing is difficult to understand as written:

Spoofing attacks

      With IPv6 ingress filtering effective in the Domain [RFC3704], and
      with consistency checks between 4rd IPv4 and IPv6 addresses of
      Section 4.5, no spoofing opportunity in IPv4 is introduced by 4rd.

I'm not exactly sure what is meant, otherwise, I'd suggest text.

Here is a link to the SecDir review:
https://www.ietf.org/mail-archive/web/secdir/current/msg05134.html

Thank you.

[Ballot comment]
I find it a dis-service to the community for the softwire WG to put forth multiple solutions that solve essentially the same problem (https://mailarchive.ietf.org/arch/msg/ietf/jcscmIHmAQSvXLAlLLvfhnC2P8A).  I believe the confusion caused by a myriad of solutions in this space, regardless of whether they are Standards Track or Experimental, will adversely impact vendors, operators, and end-users.  My only hope is that this confusion will speed up the transition to IPv6-only operations within the affected networks.

IESG/Authors/WG Chairs:

IANA has reviewed draft-ietf-softwire-4rd-08.  Please report any inaccuracies and respond to the reviewer's questions as soon as possible.

IANA's reviewer has questions about one of the actions requested in the IANA Considerations section. In addition, we understand that the other action cannot be completed until the expert approves it.

First, in the Options Codes registry under the Dynamic Host Configuration Protocol for IPv6 (DHCPv6) heading at

https://www.iana.org/assignments/dhcpv6-parameters/

a single new option code is to be registered as follows:

Value: [ TBD-at-registration ]
Description: OPTION_4RD
Reference: [ RFC-to-be ]

IANA understands that designated expert Ted Lemon will ask the authors for a revision.

Second, the document requests that a reserved IPv4 address to be used as the "IPv4 dummy address" reference in section Section 4.8 of this document. The authors proposed a value of 192.70.192.254 (Section 4.8), noting that "this address is taken in the /24 range that has been proposed for a similar purpose in [draft-xli-behave-icmp-address-04]." It is subject to IANA confirmation.

IANA notes that this address is available.

IANA Question -->

However, it appears that the authors want a single address and propose using a single address from a /24 requested by draft-xli-behave-icmp-address, which has now expired. If draft-xli-behave-icmp-address is revived and is likely to be approved, then IANA believes using this address would be acceptable. However, if what we are doing is "ruining" that /24 for anyone else ,then IANA would prefer to offer the authors an address from 192.0.0.0/24, which is set aside for exactly this kind of assignment.

If the authors need to take the address from a different /24 than 192.0.0.0/24, then it is also possible to have one from 192.70.192.0/24 (assuming this happens before the next scheduled allocation and that /24 isn't allocated by the algorithm). However, IANA is unable to leave 255 of the 256 addresses in that /24 in the IPv4 Recovered Address Space registry. IANA will need to move whichever /24 they use into the IANA IPv4 Special-Purpose Address Registry.

Because we need to register it in the IANA IPv4 Special-Purpose Address Registry, IANA requests that the authors provide the details needed for registration there, including the Boolean values for Source, Destination, Forwardable, Global, and Reserved-by-Protocol.

How would the authors like to proceed?

Note:  The actions requested in this document will not be completed until the document has been approved for publication as an RFC. This message is only to confirm what actions will be performed.

The following Last Call announcement was sent out:

From: The IESG
To: IETF-Announce
CC:
Reply-To: ietf@ietf.org
Sender:
Subject: Last Call:  (IPv4 Residual Deployment via IPv6 - a Stateless Solution (4rd)) to Experimental RFC


The IESG has received a request from the Softwires WG (softwire) to
consider the following document:
- 'IPv4 Residual Deployment via IPv6 - a Stateless Solution (4rd)'
  as Experimental RFC

The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf@ietf.org mailing lists by 2014-10-10. Exceptionally, comments may be
sent to iesg@ietf.org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.

Abstract


  The 4rd automatic tunneling mechanism makes IPv4 Residual Deployment
  possible via IPv6 networks without maintaining for this per-customer
  states in 4rd-capable nodes (reverse of the IPv6 Rapid Deployment of
  6rd).  To cope with the IPv4 address shortage, customer sites can be
  assigned shared public IPv4 addresses with restricted port sets. 4rd
  can also support the scenarios that customer sites are assigned full
  public IPv4 addresses or a set of public IPv4 addresses.




The file can be obtained via
http://datatracker.ietf.org/doc/draft-ietf-softwire-4rd/

IESG discussion can be tracked via
http://datatracker.ietf.org/doc/draft-ietf-softwire-4rd/ballot/


The following IPR Declarations may be related to this I-D:

  http://datatracker.ietf.org/ipr/2050/

(1) What type of RFC is being requested (BCP, Proposed Standard,
Internet Standard, Informational, Experimental, or Historic)? Why is
this the proper type of RFC? Is this type of RFC indicated in the title
page header?

Experimental. This document defines a scheme used to provide residual
IPv4 service over IPv6 access networks. It achieves this by the use of
reversible translation techniques at the entry and exit points of the
4rd domain.

(2) The IESG approval announcement includes a Document Announcement
Write-Up. Please provide such a Document Announcement Write-Up. Recent
examples can be found in the "Action" announcements for approved
documents. The approval announcement contains the following sections:

Technical Summary:

This document specifies a stateless softwire IPv4 over IPv6 Migration
Solution called 4rd. Using the 4rd solution IPv4 packets are
transparently carried across IPv6 networks (reverse of 6rd [RFC5969]
in which IPv6 packets are statelessly tunneled across IPv4 networks).
While IPv6 headers are too long to be mapped into IPv4 headers, so
that 6rd requires encapsulation of full IPv6 packets in IPv4 packets,
IPv4 headers can be reversibly translated into IPv6 headers in such a
way that, during IPv6 domain traversal, UDP packets having checksums
and TCP packets are valid IPv6 packets. IPv6-only middle boxes that
perform deep-packet- inspection can operate on them, in particular for
port inspection and web caches.


Working Group Summary:

The working group had active discussion on the draft and the current
text of the draft is representative of the consensus of the working
group.

Document Quality:

The document has received adequate review. The Document Shepherd has
no concerns about the depth or breadth of these reviews. Certain
aspects of the scheme have also been reviewed by the 6man working
group due to the concerns with the address format. These concerns were
successfully resolved.

Who is the Document Shepherd? Who is the Responsible Area Director?

Suresh Krishnan is the document shepherd. Ted Lemon is the responsible
AD.

(3) Briefly describe the review of this document that was performed by
the Document Shepherd. If this version of the document is not ready for
publication, please explain why the document is being forwarded to the IESG.

The document shepherd has reviewed the draft and finds that it is ready
to advance to the IESG. All issues that were raised in the working group
last calls have been addressed.

(4) Does the document Shepherd have any concerns about the depth or
breadth of the reviews that have been performed?

No. The document shepherd has no such concerns.

(5) Do portions of the document need review from a particular or from
broader perspective, e.g., security, operational complexity, AAA, DNS,
DHCP, XML, or internationalization? If so, describe the review that took
place.

No.

(6) Describe any specific concerns or issues that the Document Shepherd
has with this document that the Responsible Area Director and/or the
IESG should be aware of? For example, perhaps he or she is uncomfortable
with certain parts of the document, or has concerns whether there really
is a need for it. In any event, if the WG has discussed those issues and
has indicated that it still wishes to advance the document, detail those
concerns here.

There is significant overlap between the stateless softwire
solutions. The WG has discussed this overlap and the current document
set (along with the tracks) are the result of working group consensus
to do so.

(7) Has each author confirmed that any and all appropriate IPR
disclosures required for full conformance with the provisions of BCP
78 and BCP 79 have already been filed. If not, explain why?

Yes.

(8) Has an IPR disclosure been filed that references this document? If
so, summarize any WG discussion and conclusion regarding the IPR
disclosures.

Yes. An IPR disclosure has been filed on this document

https://datatracker.ietf.org/ipr/2050/

There was some discussion as to the IPR and the authors were debating the applicability of the ipr but the filer did not engage in the conversation.

https://www.ietf.org/mail-archive/web/softwires/current/msg05343.html

As the chair I reminded the thread initiator that the IETF would not
make a determination about the validity of any particular IPR claim

https://www.ietf.org/mail-archive/web/softwires/current/msg05349.html

Since France Telecom did not respond to it, the thread died down and
the WG did not discuss this further.

(9) How solid is the WG consensus behind this document? Does it
represent the strong concurrence of a few individuals, with others being
silent, or does the WG as a whole understand and agree with it?

There is strong WG consensus behind this document.

(10) Has anyone threatened an appeal or otherwise indicated extreme
discontent? If so, please summarise the areas of conflict in separate
email messages to the Responsible Area Director. (It should be in a
separate email because this questionnaire is publicly available.)

No.

(11) Identify any ID nits the Document Shepherd has found in this
document. (See http://www.ietf.org/tools/idnits/ and the Internet-Drafts
Checklist). Boilerplate checks are not enough; this check needs to be
thorough.

No errors were found on the ID nits check.

(12) Describe how the document meets any required formal review
criteria, such as the MIB Doctor, media type, and URI type reviews.

N/A

(13) Have all references within this document been identified as either
normative or informative?

Yes.

(14) Are there normative references to documents that are not ready for
advancement or are otherwise in an unclear state? If such normative
references exist, what is the plan for their completion?

No.

(15) Are there downward normative references references (see RFC 3967)?
If so, list these downward references to support the Area Director in
the Last Call procedure.

No.

(16) Will publication of this document change the status of any existing
RFCs? Are those RFCs listed on the title page header, listed in the
abstract, and discussed in the introduction? If the RFCs are not listed
in the Abstract and Introduction, explain why, and point to the part of
the document where the relationship of this document to the other RFCs
is discussed. If this information is not in the document, explain why
the WG considers it unnecessary.

No.

(17) Describe the Document Shepherd's review of the IANA considerations
section, especially with regard to its consistency with the body of the
document. Confirm that all protocol extensions that the document makes
are associated with the appropriate reservations in IANA registries.
Confirm that any referenced IANA registries have been clearly
identified. Confirm that newly created IANA registries include a
detailed specification of the initial contents for the registry, that
allocations procedures for future registrations are defined, and a
reasonable name for the new registry has been suggested (see RFC 5226).

The document requires no IANA actions.

(18) List any new IANA registries that require Expert Review for future
allocations. Provide any public guidance that the IESG would find useful
in selecting the IANA Experts for these new registries.

N/A

(19) Describe reviews and automated checks performed by the Document
Shepherd to validate sections of the document written in a formal
language, such as XML code, BNF rules, MIB definitions, etc.

N/A