[Drip] draft-ietf-drip-registries-14

[Daniel Migault <[e-mail]>]

Hi,

Please find my review for sections up to 8.1 of
draft-ietf-drip-registries-14

For these sections my impression is that the description could be more
concise. Most of the comments are nits. I believe these can be addressed
directly or discussed without creating an issue per comment ;-)

Yours,
Daniel

drip Working Group                                  A. Wiethuechter, Ed.
Internet-Draft                                        AX Enterprize, LLC
Intended status: Standards Track                                 J. Reid
Expires: 6 June 2024                                            RTFM llp
                                                         4 December 2023


         DRIP Entity Tag (DET) Identity Management Architecture
                     draft-ietf-drip-registries-14

Abstract

   This document describes the high level architecture for the
   registration and discovery of DRIP Entity Tags (DETs) using DNS.
   Discovery of DETs and their artifacts are through DRIP specific DNS
   structures and standard DNS methods.

<mglt>
I am wondering if "are through" should not be replaced by "is performed
via".
</mglt>

 A general overview of the
   interfaces required between involved components is described in this
   document with future supporting documents giving technical
   specifications.

<mglt>
The sentence above could mean to say the description is based on future
documents. The document seems to not provide much information regarding the
interfaces so I would not emphasize that aspect here, and probably remove
the text.

</mglt>

Status of This Memo

  [...]
[ ..]
1.  Introduction

   Registries are fundamental to Unmanned Aircraft System (UAS) Remote
   ID (RID).  Only very limited operational information can be
   Broadcast, but extended information is sometimes needed.  The most
   essential element of information is the UAS ID, the unique key for
   lookup of extended information in relevant registries (see Figure 4
   of [RFC9434]).

<mglt>
s/Broadcast/broadcast/gc
</mglt>

   While it is expected that DRIP Identity Management Entity (DIME)
   functions will be integrated with UAS Service Suppliers (USS)
   (Appendix A.2 of [RFC9434]), who will provide DIME-like functions is
   not yet determined in most, and is expected to vary between,
   jurisdictions.  However this evolves, the essential DIME-like
   functions (including the management of identifiers (such as the DRIP
   Entity Tag (DET))) are expected to remain the same, so are specified
   herein.

<mglt>
The long sentences and a factorization of parentheses could be clarified.
Essentially, the paragraph is saying that 1) This document assumes DIME is
handled by the USS. 2) The architecture does not prevent any other entity
from taking that role and 3) whoever takes that role will not affect the
functions of the DIME.
The use of DIME-like functions versus DIME functions need to be clarified.
To link the two paragraphs, it would probably be clarifying to have an
articulation between the UAS ID and the DET.

I propose something around:

Such extended information is retrieved from the UAS ID via the use of a
DRIP Entity Tag (DET) which is managed by the DRIP Identity Management
Entity (DIME). In this document we assume the DIME belongs to the UAS
Service Suppliers (USS) (Appendix A.2 of [RFC9434]) but DIME can be handled
by another entity as well.

</mglt>




Wiethuechter & Reid        Expires 6 June 2024                  [Page 3]

Internet-Draft             DETIM Architecture              December 2023


   While most data to be sent via Broadcast RID (Section 1.2.1 of
   [RFC9434]) or Network RID (Section 1.2.2 of [RFC9434]) is public,
   much of the extended information in registries will be private.

<mglt>

I do not see registry being used in a context of DNS registry. That said
the document deals with DNS so this can be confusing. Assuming this is not
a DNS registry, I suggest to clarify explicitly that registries are not
related to registries/registrars.


</mglt>

  As
   discussed in Section 7 of [RFC9434], Authentication, Attestation,
   Authorization, Access Control, Accounting, Attribution, and Audit
   (AAA) for registries is essential, not just to ensure that access is
   granted only to strongly authenticated, duly authorized parties, but
   also to support subsequent attribution of any leaks, audit of who
   accessed information when and for what purpose.

<mglt>
Is-it AAA or AAAACAAA ?

Is registry the right terminology ? Here registrar seems more appropriated.
</mglt>

  As specific AAA
   requirements will vary by jurisdictional regulation, provider
   choices, customer demand, etc., they are left to specification in
   policies, which should be human readable to facilitate analysis and
   discussion, and machine readable to enable automated enforcement,
   using a language amenable to both (e.g., eXtensible Access Control
   Markup Language (XACML)).

<mglt>
I am finding the text which "should be ... a bit out of scope.
</mglt>

   The intent of the access control requirements on registries is to
   ensure that no member of the public would be hindered from accessing
   public information, while only duly authorized parties would be
   enabled to access private information.  Mitigation of Denial of
   Service (DoS) attacks and refusal to allow database mass scraping
   would be based on those behavior, not on identity or role of the
   party submitting the query per se, but querant identity information
   might be gathered (by security systems protecting DRIP
   implementations) on such misbehavior.

<mglt>

After the mention of public and private information, a lot of text is
describing or listing AAA* which is related to private information. Then
the paragraph above details how public and private information are handled,
followed by what is needed for public information.

I do not think we should describe how to handle DDoS attacks...

   I suggest to rephrase this as follows:

   <handling of public / private information>
   The intent of the access control requirements on registries is to
   ensure that no member of the public would be hindered from accessing
   public information, while only duly authorized parties would be
   enabled to access private information.

   <public information>
   To ensure public information remains available to the public, the
registry is expected to provide a robust and reliable service...
   Mitigation of Denial of
   Service (DoS) attacks and refusal to allow database mass scraping

   <private information>
   To protect private information, as specific AAA requirements.....
</mglt>

   Registration under DRIP is vital to manage the inevitable collisions
   in the hash portion of the DET (Section 9.5 of [RFC9374]).  Forgery
   of a DET is still possible, but including it as a part of a public
   registration mitigates this risk.

<mglt>

I am not sure "Registration under DRIP" has been defined and will be
clearly understood by the reader. Inevitable discussion seems also to
contradict 9374 section 9.5 where collisions are mentioned to have a low
probability. I think what we want to say here is that Registration is
necessary to guarantee the uniqueness of the DET and thus to ensure the
extended information is bound to the UAS ID.


</mglt>

   This document creates the DRIP registration and discovery ecosystem
<mglt>
ecosystem is quite vague. architecture, protocols are more in line with
what we specify at the IETF.
</mglt>

   focusing on the DET.  This

<mglt>

   It is unclear to me what "This" relates to. I suspect This stands for a
registration/discovery protocol as an architecture is not supported by
components.

</mglt>

SHOULD support all components in the
   ecosystem (e.g., Unmanned Aircraft (UA), Registered Assigning
   Authority (RAA), Hierarchical HIT Domain Authority (HDA), Ground
   Control Station (GCS), and USS) that can use a DET.

   This document uses the Concise Data Definition Language (CDDL)
   [RFC8610] for describing the registration data.

2.  Abstract Process and Reasoning

   In DRIP each entity (DIME, Operator, UA, etc.) is expected to
   generate a DET [RFC9374] on the local device their key is expected to
   be used.

<mglt>

Just for my understanding, reading this sentence it seems that one UA has
multiple DET. I understand it is possible, but it seems to me that the
simple case is a UA having a SINGLE UAS ID which is registered as DET.
Depending on the situation the UAS ID (DET) can be registered/generated by
different entities. If that is correct, I think the paragraph should be
rephrased.

</mglt>

  These are registered with a Public Information Registry
   (e.g.  DNS) within the hierarchy along with whatever data is required
   by the cognizant CAA and the DIME.

<mglt>

I am not familiar with "Public Information Registry". I understand we may
not want to stick to DNS.... but I think given what we have now we should
say this is the DNS clearly.
The text seems to say registration involves the CAA and the DIME. I tend to
think that the UA is registered to the DIME that complies with the CAA. Is
that correct ?

</mglt>

Any Personally Identifiable
   Information (PII) is stored in a Private Information Registry



Wiethuechter & Reid        Expires 6 June 2024                  [Page 4]

Internet-Draft             DETIM Architecture              December 2023


   protected through industry practice AAA or stronger.

<mglt>
s/industry practice AAA or stronger/AAA/gc

industry practice seems to indicate we will stay with whatever exists, but
stronger means we will go beyond what exists. This contradicts the first
"industry practice". It seems clearer to me to remove that text.

</mglt>

  In response,
   the entity will obtain an endorsement from the DIME proving such
   registration.

<mglt>
I think that when we mentioned the UA registered to the DIME, implicitly we
expect a confirmation, so I do not see this as very useful information.
</mglt>

   Manufacturers that wish to participate in DRIP should not only
   support DRIP as a Session ID

<mglt>
Probably we should provide a reference to Session ID. Note also that it
seems to me this is referenced as Specific Session ID. (UAS type 4). If
that is the same entity maybe we should be coherent with the previous docs.

</mglt>

type for their aircraft but could also
   generate a DET then encode it as a Serial Number (Section 4.2 of
   [RFC9374]).

<mglt>

There are a lot of should /could. As these are not expressed in capital
letters, I tend to say these are pure speculation and are here as
informative. I tend to think we do not need to be so cautious as long as we
clearly mention this is an illustrative example on how we expect this will
work. With such an introduction the description can be straight forward.

</mglt>

  This would allow aircraft under CAA mandates to fly only
   ID Type 1 (Serial Number) could still use DRIP and most of its
   benefits.
<mglt>
I do not understand the sentence. I am reading "under CAA mandates to fly
only ID Type1" as one groupe so the sentence sounds to me This would allow
aircraft [..] could still use DRIP.... I suspect this is a mix between
"This would allow aircraft to use DRIP..." or" Aircrafts could still...."
As you know I am not native english so that might be correct also.
</mglt>

 Even if DRIP is not supported for Serial Numbers by a
   Manufacturer it is hoped that they would still run a DIME to store
   their Serial Numbers and allow look ups for generic model
   information.  This look up could be especially helpful in UTM for
   Situational Awareness when an aircraft flying with a Serial Number is
   detected and allow for an aircraft profile to be displayed.

<mglt>
"It is hoped" is too speculative in my opinion.
s/Manufacturer/manufacturer
</mglt>

   Operators are registered with a number of registries or their
   regional RAA.  This acts as a verification check when a user performs
   other registration operations; such as provisioning an aircraft with
   a new Session ID.  It is an open question if an Operator registers to
   their CAA (the RAA's direct HDA) or multiple USS's (HDA's).  PII of
   the Operator would vary based on the CAA they are under and the DIME.

   Finally, aircraft that support using a DET would provision per flight
   to a USS, proposing a DET to the DIME to generate a binding between
   the aircraft (Session ID, Serial Number, and Operational Intent),
   operator and DIME.  The aircraft then follows [drip-auth] to meet
   various requirements from [RFC9153] during a flight.

3.  Terminology

3.1.  Required Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.

3.2.  Additional Definitions

   This document makes use of the terms (PII, USS, etc.) defined in
   [RFC9153].  Other terms (DIME, Endorsement, etc.) are from [RFC9434],
   while others (RAA, HDA, etc.) are from [RFC9374].







Wiethuechter & Reid        Expires 6 June 2024                  [Page 5]

Internet-Draft             DETIM Architecture              December 2023


3.3.  Text Conventions

   When talking about a DIME in documents it should be referred to as
   the role it is serving.  For example a CAA level DIME running
   services both as an RAA (its primary role in the hierarchy) and as an
   HDA (optionally) would be be referred to "RAA" when performing its
   RAA duties and "HDA" when performing its HDA duties.  The rest of the
   document will follow this convention unless verbosity or clarity is
   needed.

4.  DIME Roles

   [RFC9434] defines the DRIP Identity Management Entity (DIME) as an
   entity that vets Claims and/or Evidence from a registrant and
   delivers, to successful registrations, Endorsements and/or
   Certificates in response.  The DIME encompasses various logical
   components and can be classified to serve a number of different
   roles, which are detailed in the following subsections.  The general
   hierarchy of these initial roles (some highly specialized and
   predetermined for the UAS use case) are illustrated in Figure 1.

                          +----------+
                          |   Apex   o--------.
                          +-o------o-+        |
                            |      |          |
          ******************|******|**********|******************
                            |      |          |
                      +-----o-+  +-o-----+  +-o-----+
          RAAs        |  MCA  |  |  INN  |  |  RAA  |
                      +---o---+  +---o---+  +---o---+
                          |          |          |
          ****************|**********|**********|****************
                          |          |          |
                      +---o---+  +---o---+  +---o---+
          HDAs        |  MAA  |  |  HDA  |  |  HDA  |
                      +-------+  +-------+  +-------+

                     Figure 1: DIME Roles and Hierarchy
<mglt>
I think it would be good to clarify the meaning of the acronyms.
We should also explain what RAA/HDA differs from the generic RAAs/HDAs.
DET defines RAA and HDA as some bits, and it seems that some sort of
delegation exists between RAA and HDAs. However, there are no bits for Apex
and as such Figure 1 does not seem to represent that delegation induced by
the DET fields but instead as a specific "administrative entity" that uses
special bits values for RAA and HDA. Maybe that is clarified after, but the
current description is missing to specify that it represents business
entities or administrations. All of them will be encoded on the RAA and HDA
bits.


</mglt>

4.1.  Apex

   The Apex is a special DIME role that holds the values of RAA=0-3 and
   HDA=0.
 It serves as the branch point from the larger DNS system in
   which DETs are defined.  The Apex is the owner of the IPv6 prefix
   portion of the DET associated with it (2001:30/28) which is assigned
   by IANA from the special IPv6 address space for ORCHIDs.

<mglt>
I think I am missing the text that explains briefly why we need to have an
Apex. If that is the administrative contact of the prefix why do we need to
assign a specific RAA/HDA code point.
</mglt>



Wiethuechter & Reid        Expires 6 June 2024                  [Page 6]

Internet-Draft             DETIM Architecture              December 2023


   The Apex manages all delegations and allocations of the DET's RAA to
   various parties.  Allocations of RAAs SHOULD be done in contiguous
   groups of 4.

      +===================+=================+======================+
      | RAA Decimal Range | RAA Hex Range   | Status               |
      +===================+=================+======================+
      | 0 - 3             | 0x0000 - 0x0003 | Apex                 |
      +-------------------+-----------------+----------------------+
      | 4 - 3999          | 0x0004 - 0x0F9F | ISO 3166-1 Countries |
      |                   |                 | (Section 4.2.1)      |
      +-------------------+-----------------+----------------------+
      | 4000 - 16375      | 0x1000 - 0x3FFF | Reserved             |
      +-------------------+-----------------+----------------------+
      | 16376 - 16383     | 0x3FF8 - 0x3FFF | DRIP WG Experimental |
      |                   |                 | Use                  |
      +-------------------+-----------------+----------------------+

                                 Table 1

      Note: that the first column of this table is _decimal_ values
      *not* _hexadecimal_.

   RAA values of 0 (0x0000) to 3 (0x0003) are reserved to the Apex
   exclusively.

   The Experimental range of 16376 (0x3FF8) to 16383 (0x3FFF), eight (8)
   RAAs, is allocated to the DRIP working group itself. 16376 to 16379
   are setup by DRIP experts to act as RAAs for potential HDA users to
   test against.  RAA 16376 is already "in use" with driptesting.org.
   The rest of the range (16377 to 16383) are reserved to be allocate by
   the DRIP experts to agencies that wish to test.
<mglt>
This should be in the IANA section so a reference to that section is
probably better to avoid repeated and contradicting wording. The iANA
section needs to have clear instructions on how to register (expert review)
with parameters and procedure to follow. See RFC 8126 for more details.

</mglt>

4.2.  Registered Assigning Authority (RAA)

   RAA's are the upper hierarchy in DRIP (denoted by a 14-bit field,
   i.e. 16,384 RAAs, of an DET).  An RAA is a business or organization
   that manages a DIME of HDAs (Section 4.3).  Most are contemplated to
   be Civil Aviation Authorities (CAA), such as the Federal Aviation
   Authority (FAA), that then delegate HDAs to manage their National Air
   Space (NAS).  This is does not preclude other entities to operate an
   RAA if the Apex allows it.









Wiethuechter & Reid        Expires 6 June 2024                  [Page 7]

Internet-Draft             DETIM Architecture              December 2023


   An RAA must provide a set of services to allocate HDAs to
   organizations.  It must have a public policy on what is necessary to
   obtain an HDA.  It must maintain a DNS zone minimally for discovering
   HID RVS servers.  All RAA's have a single reserved HDA value: 0
   (0x0000) for itself to support various functions or services.  Other
   HDA values can be allocated or reserved per RAA policy.

<mglt>
must is correct but I tend to think we should avoid saying must when we
have no authority on it.
</mglt>

4.2.1.  ISO 3166-1 Numeric Nations (INN)

   The RAA range of 4 (0x0004) to 3999 (0x0F9F) are reserved for CAAs
   using the ISO 3166-1 Numeric Nation Code.  The RAA can be derived
   from the ISO 3166-1 numeric code by multiplying the value by 4 (i.e.
   raa_code = iso_code * 4).  Four contiguous values (raa_code + 0,
   raa_code + 1, raa_code + 2 and raa_code + 3) are used in a single
   allocation.  The inverse (RAA to ISO) works out as: iso_code =
   floor(raa_code / 4).

   As an example the United States has an ISO 3166-1 Numeric Code of
   840.  This derives the following RAAs: 3360, 3361, 3362 and 3363.

   It should be noted that the range of codes from 900 to 999 are
   defined as "user assigned code elements" without specific claimant
   predefined in the RAA space.  Withdrawn and other special codes also
   do not have predetermined claimants.

<mglt>
I am wondering if we wanted to allocate multiple RAA per country. If that
is not the case and we are allocating 4 code points for convenience, we may
reserve 2 bits. I know this has been discussed.

I am expecting the term "user assigned code element". It is unclear to me
what it means, but I suspect we do not want anyone but ISO to assign these
code points. If that is the case, maybe that should be clearly stated.


</mglt>

   How a CAA handles their 4 allocations are out of scope of this
   document.  Control of these values are expected to be claimed by
   their respective owner.  How a claim is vetted and validated is out
   of scope of this document.  Protection against fraudulent claims of
   one of these values is out of scope for this document.

      Note: A single entity may control more than one NAS (for example
      LU and BE being covered by Skeyes.be) and would manage two
      allocation spaces.  How this is claimed and handled is out of
      scope for this document.

4.3.  Hierarchial HIT Domain Authority (HDA)

   An HDA may be an USS, ISP, or any third party that takes on the
   business to register the actual entities that need DETs.  This
   includes, but is not limited to UA, GCS, UAS Operators and
   infrastructure (such as Supplemental Data Service Providers).  It
   should also provide needed UAS services including those required for
   HIP-enabled devices (e.g.  RVS).

   A primary function of HDAs for DRIP, in the context of UAS RID is the
   binding between a UAS Session ID (for DRIP the DET) and the UA Serial
   Number.  The Serial Number MUST have its access protected to allow



Wiethuechter & Reid        Expires 6 June 2024                  [Page 8]

Internet-Draft             DETIM Architecture              December 2023


   only authorized parties to obtain it.  The Serial Number MUST be
   protected in a way only the authorized party can decrypt.  As part of
   the UTM system HDAs can also hold a binding between a UAS ID (Serial
   Number or Session ID) and an Operational Intent.  They may either be
   a direct logical part of a UAS Service Supplier (USS) or be a UTM
   wide service to USS's.

   The HDA is a 14-bit field (16,384 HDAs per RAA) of a DET assigned by
   an RAA.  An HDA should maintain a set of RVS servers for UAS clients
<mglt>
is it should or MUST with the currently defined DRIP ?
</mglt>
   that may use HIP.  How this is done and scales to the potentially
   millions of customers are outside the scope of this document.  This
   service should be discoverable through the DNS zone maintained by the
   HDA's RAA.

   An RAA may assign a block of values to an individual organization.
   This is completely up to the individual RAA's published policy for
   delegation.  Such policy is out of scope.

<mglt>
out of scope of this document.
</mglt>

5.  DIME Architecture

   The DIME, in any of its roles (Section 4), is comprised of a number
   of logical components that are depicted in Figure 2.  Any of these
   components could be delegated to other entities as a service both co-
   located or remote.  For example:

   *  The Name Server component could be handled by a well-established
      DNS registrar/registry with the DRIP Provisioning Agent (DPA)
      (Section 5.1) interfacing to them
      -  Either the DPA or the Registry/Name Server interfaces to the
         DRIP Information Agent (DIA)

   *  The DPA, Registry, and Name Server may all be co-located in one
      implementation with an interface to a DIA offered by another
      organization from any one of the co-located components
















Wiethuechter & Reid        Expires 6 June 2024                  [Page 9]

Internet-Draft             DETIM Architecture              December 2023


     +--------------------+
     | Registering Client |
     +---------o----------+
               |
     **********|******************************************************
     *         |     DRIP Identity Management Entity (DIME)          *
     *         |                                                     *
     *  +------o-------+      +-------------+      +--------------+  *
     *  | DRIP         |      |             |      |              |  *
     *  | Provisioning o------o             |      |              |  *
     *  | Agent (DPA)  |      |             |      |              |  *
     *  +-------o------+      |             |      |              |  *
     *          |             |             |      |              |  *
     *          |             | DRIP        |      | Registration |  *
     *  +-------o--+          | Information o------o Data         |  *
     *  | Registry o----------o Agent (DIA) |      | Directory    |  *
     *  +-------o--+          |             |      | Service      |  *
     *          |             |             |      | (RDDS)       |  *
     *          |             |             |      |              |  *
     *  +-------o----------+  |             |      |              |  *
     *  | Name Server (NS) |  |             |      |              |  *
     *  +------o-----------+  +-----o-------+      +------o-------+  *
     *         |                    |                     |          *
     *         |                    |                     |          *
     **********|********************|*********************|***********
               |                    |                     |
               |            +-------o-------+             |
               '------------o Lookup Client o-------------'
                            +---------------+

                     Figure 2: DIME Logical Components

5.1.  DRIP Provisioning Agent (DPA)

   The DPA performs the important task of vetting information coming
   from clients wishing to register and then delegate (internally or
   externally) various items to other components in the DIME.

   A standard interface MUST be provided for clients to access.  An
   HTTPS based interface is RECOMMENDED.  This interface specification
   is out of scope for this document.

<mglt>
I am finding it quite strange to recommend HTTPS though we do not define
the interface. I would remove such a recommendation.
</mglt>

   There MUST be an interface from the DPA to a Registry (Section 5.2)
   component which handles the DNS specific requirements of the DIME as
   defined by the Registry.  There MAY also be interface from the DPA to
   a DRIP Information Agent (Section 5.4) as defined by the DIA.




Wiethuechter & Reid        Expires 6 June 2024                 [Page 10]

Internet-Draft             DETIM Architecture              December 2023


                       +-------------+
                       | Registering |
                       |   Client    |
                       +------o------+
                              |
                              | HTTPS
                              |
                              |
                           +--o--+           +-----+
                           | DPA o-----------o DIA |
                           +--o--+    TBD    +-----+
                              |
                              |
                              | HTTPS or EPP
                              |
                       +------o---+
                       | Registry |
                       +----------+

                      Figure 3: DPA Interface Mapping

<mglt>
The text does not mention EPP, it would be good to specify EPP as an
example or typical protocol that can be used. I believe that HTTPS or EPP
should be EPP over HTTPS.

I do not see what information Figure 3 provides that is not mentioned in
Figure 2 and so my preference would be to have a single Figure 2. I suggest
removing Figure 3.

</mglt>

5.2.  Registry

   The Registry component handles all the required DNS based
   requirements of the DIME to function for DRIP.  This includes the
   registration and maintenance of various DNS Resource Records.

   A standardized interface MUST be implemented for interactions with
   the DPA (Section 5.1).  This interface MAY be over HTTPS using JSON/
   CBOR encoding or MAY use the Extensional Provisioning Protocol (EPP)
   [RFC5730].  The detailed specification of either of these interfaces
   is out of scope for this document.

<mglt>
I am finding it hard to mandate something we do not specify. In addition,
the DIME may use its own proprietary interfaces for its internal
components. So I believe these interfaces should only be mentioned as
examples. Maybe that would be useful to mention them in the Figure 2 and
indicate these are provided as examples. This prevents having to define the
interface at two places or picking one place and being told the information
is missing at the other place.
</mglt>

   There MAY be interface from the Registry to a DRIP Information Agent
   (Section 5.4) as defined by the DIA.
















Wiethuechter & Reid        Expires 6 June 2024                 [Page 11]

Internet-Draft             DETIM Architecture              December 2023


                          +-----+
                          | DPA |
                          +--o--+
                             |
                             | HTTPS or EPP
                             |
                             |
                      +------o---+           +-----+
                      | Registry o-----------o DIA |
                      +-----o----+    TBD    +-----+
                            |
                            |
                            | TBD
                            |
                        +---o--+
                        |  NS  |
                        +------+

                    Figure 4: Registry Interface Mapping

<mglt>
I suggest removing figure 4.
</mglt>

5.3.  Name Server (NS)

   The interface of the Name Server to any component (nominally the
   Registry) in a DIME is out of scope as typically they are
   implementation specific.

<mglt>
I suggest replacing The interface of the Name Server to any component
(nominally the
   Registry)." by "The interface of the Name Server to The Registry".
</mglt>

      Author Note: This may be very important here as we should not
      preclude a USS from running his own Name Server but they are not
      DNS experts and will need guidance or at least pointers to it to
      not mess it up.  Such as SOA and NS formats to allow delegation if
      acting as an RAA.

<mglt>
It seems to be beyond the scope of the architecture document. There is
balance between the specific needs and DNS current practice. It also
beleive that is reasonable to follow the BCP and that we do not need to go
into such details.

What seems to me more important is to specify what kind of information teh
NS is hosting.
</mglt>



















Wiethuechter & Reid        Expires 6 June 2024                 [Page 12]

Internet-Draft             DETIM Architecture              December 2023


                         +----------+
                         | Registry |
                         +-----o----+
                               |
                               |
                               | TBD
                               |
                           +---o--+
                           |  NS  |
                           +--o---+
                              |
                              |
                              | DNS Query/Response
                              |
                         +----o----------+
                         | Lookup Client |
                         +---------------+

                  Figure 5: Name Server Interface Mapping

<mglt>
Figure to be removed.
</mglt>

5.4.  DRIP Information Agent (DIA)

   The DIA is the main component handling requests for information from
   entities outside of the DIME.  Typically this is when an Observer
   looks up a Session ID from an UA and gets pointed to the DIA to
   obtain information not available publicly (i.e. via DNS).

   The information contained in the DIA is generally more oriented
   around the Operator of a given UAS and is thus classified as
   Personally Identifiable Information (PII).  To protect the privacy of
   an Operator of the UAS this information is not publicly accessible
   and is only available behind policy driven differentiated access
   mechanisms (see Section 7).

<mglt>
To protect .... has already been mentioned in the introduction and section
7. This is probably sufficient.
</mglt>

   For DRIP, the Registration Data Access Protocol (RDAP) ([RFC7480],
   [RFC9082] and [RFC9083]) is the selected protocol to provide policy
   driven differentiated access for queries of information from clients.
<mglt>
We need to be more normative here.
</mglt>

   There MUST be a standardized interface for the DPA or Registry to
   add, update or delete information into the DIA.  Specific details for
   these interfaces are out of scope for this document.

   An interface defined by the Registration Data Directory Service
   (RDDS) (Section 5.5) is also required as specified by the RDDS.

<mglt>
The two paragraphs above do not provide significant information in my
opinion, thus I would remove them. I believe that what information is
expected from the Registry or DPA is missing and should be added.

</mglt>





Wiethuechter & Reid        Expires 6 June 2024                 [Page 13]

Internet-Draft             DETIM Architecture              December 2023


                                    +-----+
                                    | DPA |
                                    +--o--+
                                       |
                                       |
                                       | TBD
                                       |
             +----------+    TBD    +--o--+             +------+
             | Registry o-----------o DIA o-------------o RDDS |
             +----------+           +--o--+     TBD     +------+
                                       |
                                       |
                                  RDAP |
                                       |
                               +-------o-------+
                               | Lookup Client |
                               +---------------+

                      Figure 6: DIA Interface Mapping

5.5.  Registration Data Directory Service (RDDS)

   This is the primary information database for the DIA.  An interface
   MUST be provided to the DIA but its specification is out of scope for
   this document.

                                +-----+
                                | DIA |
                                +--o--+
                                   |
                                   |
                                   | TBD
                                   |
                               +---o--+
                               | RDDS |
                               +--o---+
                                  |
                                  |
                                  | RDAP
                                  |
                             +----o----------+
                             | Lookup Client |
                             +---------------+

                      Figure 7: RDDS Interface Mapping






Wiethuechter & Reid        Expires 6 June 2024                 [Page 14]

Internet-Draft             DETIM Architecture              December 2023


6.  Registration/Provisioning Process

   The general process for a registering party is as follows:

   1.  Verify input Endorsement(s) from registering party

   2.  Check for collision of DET and HI

   3.  Populate Registry/Name Server with resource record(s)

   4.  Populate RDDS via DIA with PII and other info

   5.  Generate and return Endorsement(s)

   In the following subsections an abbreviated form of Section 5 using
   co-located components is used to describe the flow of information.
   The data elements being transmitted between entities is marked
   accordingly in each figure for the specific examples.

   Each section has an associated appendix (Appendix D) containing DNS
   examples.

6.1.  Operator

   Provided either by USS or CAA run HDAs.
<mglt>
I suspect something is missing.
</mglt>

  Regulation might require
   interaction between them.  An Operator can request that certain
   information normally generated and provisioned into DNS be omitted
   due to privacy concerns.























Wiethuechter & Reid        Expires 6 June 2024                 [Page 15]

Internet-Draft             DETIM Architecture              December 2023


                    +----------+
                    | Operator |
                    +--o---o---+
                       |   ^
                   (a) |   | (b)
                       |   |
                *******|***|*****************************
                *      |   |    DIME:HDA                *
                *      |   |                            *
                *      v   |             +----------+   *
                *   +--o---o--+          |          |   *
                *   |   DPA   o--------->o          |   *
                *   +----o----+   (d)    |          |   *
                *        |               |          |   *
                *        | (c)           | DIA/RDDS |   *
                *        v               |          |   *
                *   +----o--------+      |          |   *
                *   | Registry/NS |      |          |   *
                *   +-------------+      |          |   *
                *                        +----------+   *
                *                                       *
                *****************************************

                (a) Operator Information,
                    Operator Self-Endorsement
                (b) Success Code,
                    Generic Endorsement: HDA on Operator
                (c) HIP RR, DET RR, TLSA RR, URI RR, PTR RR
                (d) Operator Information

                Note: (c) MAY be requested by the Operator
                      to be omitted due to PII concerns.

        Figure 8: Example DIME:HDA with Operator (DET) Registration

   The definition of Operator Information is out of scope of this
   document and left to local regulations (both in its format and
   contents).

6.2.  Session ID

   Session IDs are generally handled by HDAs.  In Figure 9 the UAS
   comprises of an unmanned aircraft and a Ground Control Station (GCS).
   Both parties are involved in the registration process.







Wiethuechter & Reid        Expires 6 June 2024                 [Page 16]

Internet-Draft             DETIM Architecture              December 2023


                    +---------+
                    |   UAS   |
                    +--o---o--+
                       |   ^
                   (a) |   | (b)
                       |   |
                *******|***|*****************************
                *      |   |    DIME: HDA               *
                *      |   |                            *
                *      v   |             +----------+   *
                *   +--o---o--+          |          |   *
                *   |   DPA   o--------->o          |   *
                *   +----o----+   (d)    |          |   *
                *        |               |          |   *
                *        | (c)           | DIA/RDDS |   *
                *        v               |          |   *
                *   +----o--------+      |          |   *
                *   | Registry/NS |      |          |   *
                *   +-------------+      |          |   *
                *                        +----------+   *
                *                                       *
                *****************************************

                (a) Mutual Endorsement: HDA on GCS,
                    Generic Endorsement: GCS on UA,
                    Session ID Information
                (b) Success Code,
                    Broadcast Endorsement: HDA on UA,
                    Generic Endorsement: HDA on UAS
                (c) HIP RR, DET RR, TLSA RR, URI RR, PTR RR
                (d) Session ID Information

       Figure 9: Example DIME:HDA with Session ID (DET) Registration

   Through mechanisms not specified in this document the Operator should
   have methods (via the GCS) to instruct the unmanned aircraft onboard
   systems to generate a keypair, DET and Self-Endorsement: UA.  The
   Self-Endorsement: UA is extracted by the Operator onto the GCS.

   The GCS is already pre-provisioned and registered to the DIME with
   its own keypair, DET, Self-Endorsement: GCS and Generic Endorsement:
   HDA on GCS.  The GCS creates a new Generic Endorsement: GCS on UA and
   also creates Mutual Endorsement: HDA on GCS.  These new endorsements
   along with Session ID Information are sent to the DIME via a secure
   channel.






Wiethuechter & Reid        Expires 6 June 2024                 [Page 17]

Internet-Draft             DETIM Architecture              December 2023


   The GCS injects the Broadcast Endorsement: HDA on UA securely into
   the unmanned aircraft.  Endorsement: HDA on GCS is securely stored by
   the GCS.

      Note: in Figure 9 the Session ID Information is expected to
      contain the Serial Number along with other PII specific
      information (such as UTM data) related to the Session ID.

   Session ID Information is defined as the current model:

   sessionid_info = {
       serial: tstr .size 20,
       session_id: tstr,
       operational_intent: tstr,
       intent_src: tstr,
       operator_id: tstr,
       session_context: tstr,
       * tstr: any
   }

   Future standards or implementations MAY add other keys to this list
   (for local features and/or local regulation).

6.2.1.  UA Based Session ID

   There may be some unmanned aircraft that have their own Internet
   connectivity allowing them to register a Session ID themselves
   without outside help from other devices such as a GCS.  When such a
   system is in use its imperative that the Operator has some method to
   create the Generic Endorsement: Operator on UA to send to the DIME.
   The process and methods to perform this are out of scope for this
   document but MUST be done in a secure fashion.

<mglt>
s/its/it is/

</mglt>

6.2.2.  UAS Based Session ID

   Most unmanned aircraft will not have their own Internet connectivity
   but will have a connection to a GCS.  Typically a GCS is an
   application on a user device (such as smartphone) that allow the user
   to fly their aircraft.  For the Session ID registration the DIME MUST
   be provided with an Generic Endorsement: GCS on UA which implies
   there is some mechanism extracting and inserting information from the
   unmanned aircraft to the GCS.  These methods MUST be secure but are
   out of scope for this document.

   With this system it is also possible to have the GCS generate the DET
   based Session ID and insert it securely into the unmanned aircraft
   after registration is done.  This is NOT RECOMMENDED as this
   invalidates the objective of the asymmetric cryptography in the



Wiethuechter & Reid        Expires 6 June 2024                 [Page 18]

Internet-Draft             DETIM Architecture              December 2023


   underlying DET as the private key MAY get in the possession of
   another entity other than the unmanned aircraft.  See Section 12.2
   for more details.

6.3.  Child DIME

   Handled by the Apex and RAA's.  This is an endpoint that handles
   dynamic registration (or key roll-over) of lower-level DIMEs (RAAs to
   Apex and HDAs to RAAs) in the hierarchy.

                    +---------------+
                    |   DIME: HDA   |
                    +--o---o--------+
                       |   ^
                   (a) |   | (b)
                       |   |
                *******|***|*****************************
                *      |   |    DIME: RAA               *
                *      |   |                            *
                *      v   |             +----------+   *
                *   +--o---o--+          |          |   *
                *   |   DPA   o--------->o          |   *
                *   +----o----+   (d)    |          |   *
                *        |               |          |   *
                *        | (c)           | DIA/RDDS |   *
                *        v               |          |   *
                *   +----o--------+      |          |   *
                *   | Registry/NS |      |          |   *
                *   +-------------+      |          |   *
                *                        +----------+   *
                *                                       *
                *****************************************

                (a) Self-Endorsement: HDA,
                    HDA Information or
                    Generic Endorsement: old HDA, new HDA
                (b) Success Code,
                    Broadcast Endorsement: RAA on HDA
                (c) HIP RR, DET RR, TLSA RR, URI RR, PTR RR
                (d) HDA Information

           Figure 10: Example DIME:RAA with DIME:HDA Registration









Wiethuechter & Reid        Expires 6 June 2024                 [Page 19]

Internet-Draft             DETIM Architecture              December 2023


   It should be noted that this endpoint DOES NOT hand out dynamically

<mglt>
DOES NOT does not seem to be a standard terminology. **does not** or __does
not__ may be used instead if we really need it. That said, you can keep it
as is and see if anyone raises an issue.
</mglt>

   RAA/HDA values to systems that hit the endpoint.  This is done out-
   of-band through processes specified by local regulations and
   performed by cognizant authorities.  The endpoint MUST NOT accept
   queries it is not previously informed of being expected via
   mechanisms not defined in this document.

   It is OPTIONAL to implement this endpoint.  This MAY be used to
   handle lower-level DIME key roll-over.

7.  Differentiated Access Process

   Per [RFC9434] all information classified as public is stored in a
   datastore protected using some form of differentiated access (i.e.
   AAA) to satisfy REG-2 from [RFC9153].

   Differentiated access, as a process, is a requirement for DIMEs as
   defined in [RFC9153] by the combination of PRIV-1, PRIV-3, PRIV-4,
   REG-2 and REG-4.  [RFC9434] further elaborates on the concept by
   citing RDAP (from [RFC7480], [RFC9082] and [RFC9083]) as a potential
   means of fulfilling this requirement.

   Typically the cognizant authority is the primary querant of private
   information from a DIME if a Session ID is reported (the case of the
   owner of the private information is ignored for the moment).  This
   capability MAY be delegated to other parties at the authorities
   discretion (be it to a single user or many), thus requiring a
   flexible system to delegate, determine and revoke querent access
   rights for information.  XACML MAY be a good technology choice for
   this flexibility.

   It is noted by the authors that as this system scales the problem
   becomes a, well known and tricky, key management problem.  While
   recommendations for key management are useful they are not
   necessarily in scope for this document as best common practices
   around key management should already be mandated and enforced by the
   cognizant authorities in their existing systems.  This document
   instead focuses on finding a balance for generic wide-spread
   interoperability between DIMEs with authorities and their existing
   systems in a Differentiated Access Process (DAP).

   A system where cognizant authorities would require individual
   credentials to each HDA is not scalable, nor practical.  Any change
   in policy would require the authority to interact with every single
   HDA (active or inactive) to grant or revoke access; this would be
   tedious and prone to mistakes.  A single credential for a given
   authority is also strongly NOT RECOMMENDED due to the security
   concerns it would entail if it leaked.



Wiethuechter & Reid        Expires 6 June 2024                 [Page 20]

Internet-Draft             DETIM Architecture              December 2023


   A zero-trust model would be the most appropriate for a DAP; being
   highly flexible and robust.  Most authorities however use "oracle"
   based systems with specific user credentials and the oracle knowing
   the access rights for a given user.  This would require the DAP the
   have some standard mechanism to locate and query a given oracle for
   information on the querent to determine if access is granted.

   DRIP has no intention to develop a new "art" of key management,
   instead hoping to leverage existing systems and be flexible enough to
   adapt as new ones become popular.

8.  DRIP in the Domain Name System

   Per [RFC9434] all information classified as public is stored in the
   DNS to satisfy REG-1 from [RFC9153].

   The apex for domain names MUST be under the administrative control of
   ICAO, the international treaty organization providing the critical
   coordination platform for civil aviation.

<mglt>
It would be usefull to spell out ICAO. It is probably not appropriated to
be normative about ICAO (see below).
</mglt>

 ICAO SHOULD be responsible
   for the operation of the DNS-related infrastructure for these domain
   name apexes.  It MAY chose to run that infrastructure directly or
   outsource it to competent third parties or some combination of the
   two.  ICAO SHOULD specify the technical and administrative criteria
   for the provision of these services: contractual terms (if any),
   reporting, uptime, SLAs (if any), DNS query handling capacity,
   response times incident handling, complaints, law enforcement
   interaction and so on.

   The delegation of civil aviation authorities to RAAs is already done
   per Section 4.2.1 using their ISO 3166-1 Numeric Codes.  Since these
   are public, any entity can stand up an RAA with that value.  ICAO
   SHOULD be the root of trust in a Endorsement or certificate chain
   that provides validation of any of these specific RAAs, in the ISO
   RAA range, thus protecting against bad actors standing up fraudulent
   RAAs.  This also ensures DRIP complies with national law and
   regulation since these are matters of national sovereignty.















Wiethuechter & Reid        Expires 6 June 2024                 [Page 21]

Internet-Draft             DETIM Architecture              December 2023


   Each national aviation authority SHOULD be responsible for the
   operation of the DNS-related infrastructure for their delegated
   subdomains.  As with the domain apexes overseen by ICAO, each
   national aviation authority MAY chose to run that infrastructure
   directly or outsource it to competent third parties or some
   combination of the two.

<mglt>
s/to competent third parties or some combination of the two//
</mglt>

  National aviation authorities SHOULD specify
   the technical and administrative criteria for the provision of these
   services: contractual terms (if any), reporting, uptime, SLAs (if
   any), DNS query handling capacity, response times, incident handling,
   complaints, law enforcement interaction and so on.  These are
   National Matters where national law/regulation prevail.  National
   policy and regulations will define how long DNS data are stored or
   archived.

   DNSSEC is strongly RECOMMENDED (especially for RAA-level and higher
   zones).

<mglt>
This is sufficient at the architectural level to simply recommend DNSSEC.
So the text below is in my opinion to be removed.
</mglt>

  When a DIME decides to use DNSSEC they SHOULD define a
   framework for cryptographic algorithms and key management [RFC6841].
   This may be influenced by frequency of updates, size of the zone, and
   policies.

8.1.  DRIP Entity Tags

   The REQUIRED mechanism is to place any information into ip6.arpa when
   using a DET.  Since the DET is an IPv6 address it can be nibble-
   reversed and used in the zone, per standard conventions.

<mglt>
I suspect that it might be more exact to say DET has the format of an IPv6
address.
It is probably better to indicate the exact reference and remove  "per
standard conventions".
</mglt>

   The prefix 2001:30/28 is registered with IANA [RFC9374] and
   3.0.0.1.0.0.2.ip6.arpa - the corresponding reverse domain - SHOULD be
   under the administrative control of the Apex.  In addition to the DNS
   infrastructure for 3.0.0.1.0.0.2.ip6.arpa, the Apex SHOULD be
   responsible for the allocation of IPv6 addresses in this prefix.  An
   addressing plan will need to be developed.

<mglt>
In my opinion, there is no normative recommendations to be provided here.
This is a description of the architecture.
</mglt>

   Distribution of HHIT (IPv6 address) blocks SHOULD be done using the
   14-bit RAA space as a framework.  The Apex SHOULD allocate blocks to
   each entity who can then assign them to HDAs in accordance with local
   law and policy.  All HDAs MUST have an IPv6 address in 2001:30/28.  A

<mglt>

I think it is more the HAD that will determine which blocks goes to which
HDA. I propose a sentence around the following words:
 The Apex allocate blocks to each RAA. Each RAA will then assign subblocks
to HDAs.
</mglt>


   discrete zone SHOULD be delegated for each HDA.  These MUST contain
   an DET resource record (Section 8.1.1) for itself.

<mglt>
I have the impression it would be clearer to explicitly indicate "These".
</mglt>

   Reverse lookups of these IPv6 addresses will translate the address
   into a domain name in the manner defined in [RFC1886].  However,
   these lookups will query for, depending on what is required: HIP,
   DET, TLSA, URI, or PTR RRTypes.

8.1.1.  DET Resource Record

-- 
Daniel Migault
Ericsson