draft-ietf-drip-arch-18.txt   draft-ietf-drip-arch-19.txt 
drip S. Card drip S. Card
Internet-Draft A. Wiethuechter Internet-Draft A. Wiethuechter
Intended status: Informational AX Enterprize Intended status: Informational AX Enterprize
Expires: 17 June 2022 R. Moskowitz Expires: 20 July 2022 R. Moskowitz
HTT Consulting HTT Consulting
S. Zhao (Editor) S. Zhao (Editor)
Tencent Tencent
A. Gurtov A. Gurtov
Linköping University Linköping University
14 December 2021 16 January 2022
Drone Remote Identification Protocol (DRIP) Architecture Drone Remote Identification Protocol (DRIP) Architecture
draft-ietf-drip-arch-18 draft-ietf-drip-arch-19
Abstract Abstract
This document describes an architecture for protocols and services to This document describes an architecture for protocols and services to
support Unmanned Aircraft System Remote Identification and tracking support Unmanned Aircraft System Remote Identification and tracking
(UAS RID), plus RID-related communications. This architecture (UAS RID), plus RID-related communications. This architecture
adheres to the requirements listed in the DRIP Requirements document. adheres to the requirements listed in the DRIP Requirements document.
Status of This Memo Status of This Memo
skipping to change at page 1, line 39 skipping to change at page 1, line 39
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on 17 June 2022. This Internet-Draft will expire on 20 July 2022.
Copyright Notice Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the Copyright (c) 2022 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/ Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document. license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components and restrictions with respect to this document. Code Components
extracted from this document must include Simplified BSD License text extracted from this document must include Revised BSD License text as
as described in Section 4.e of the Trust Legal Provisions and are described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License. provided without warranty as described in the Revised BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Overview of Unmanned Aircraft System (UAS) Remote ID (RID) 1.1. Overview of Unmanned Aircraft System (UAS) Remote ID (RID)
and Standardization . . . . . . . . . . . . . . . . . . . 3 and Standardization . . . . . . . . . . . . . . . . . . . 3
1.2. Overview of Types of UAS Remote ID . . . . . . . . . . . 4 1.2. Overview of Types of UAS Remote ID . . . . . . . . . . . 4
1.2.1. Broadcast RID . . . . . . . . . . . . . . . . . . . . 4 1.2.1. Broadcast RID . . . . . . . . . . . . . . . . . . . . 4
1.2.2. Network RID . . . . . . . . . . . . . . . . . . . . . 5 1.2.2. Network RID . . . . . . . . . . . . . . . . . . . . . 5
1.3. Overview of USS Interoperability . . . . . . . . . . . . 7 1.3. Overview of USS Interoperability . . . . . . . . . . . . 7
1.4. Overview of DRIP Architecture . . . . . . . . . . . . . . 8 1.4. Overview of DRIP Architecture . . . . . . . . . . . . . . 8
2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 10 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.1. Architecture Terminology . . . . . . . . . . . . . . . . 10 3. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 9
2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 10 3.1. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 9
2.3. Claims, Assertions, Attestations, and Certificates . . . 10 3.2. Claims, Assertions, Attestations, and Certificates . . . 10
2.4. Additional Definitions . . . . . . . . . . . . . . . . . 11 3.3. Additional Definitions . . . . . . . . . . . . . . . . . 10
3. HHIT as the DRIP Entity Identifier . . . . . . . . . . . . . 11 4. HHIT as the DRIP Entity Identifier . . . . . . . . . . . . . 10
3.1. UAS Remote Identifiers Problem Space . . . . . . . . . . 12 4.1. UAS Remote Identifiers Problem Space . . . . . . . . . . 11
3.2. HHIT as A Trustworthy DRIP Entity Identifier . . . . . . 12 4.2. HHIT as A Trustworthy DRIP Entity Identifier . . . . . . 11
3.3. HHIT for DRIP Identifier Registration and Lookup . . . . 14 4.3. HHIT for DRIP Identifier Registration and Lookup . . . . 13
3.4. HHIT as a Cryptographic Identifier . . . . . . . . . . . 14 4.4. HHIT as a Cryptographic Identifier . . . . . . . . . . . 13
4. DRIP Identifier Registration and Registries . . . . . . . . . 14 5. DRIP Identifier Registration and Registries . . . . . . . . . 13
4.1. Public Information Registry . . . . . . . . . . . . . . . 15 5.1. Public Information Registry . . . . . . . . . . . . . . . 14
4.1.1. Background . . . . . . . . . . . . . . . . . . . . . 15 5.1.1. Background . . . . . . . . . . . . . . . . . . . . . 14
4.1.2. DNS as the Public DRIP Identifier Registry . . . . . 15 5.1.2. DNS as the Public DRIP Identifier Registry . . . . . 14
4.2. Private Information Registry . . . . . . . . . . . . . . 15 5.2. Private Information Registry . . . . . . . . . . . . . . 14
4.2.1. Background . . . . . . . . . . . . . . . . . . . . . 15 5.2.1. Background . . . . . . . . . . . . . . . . . . . . . 14
4.2.2. EPP and RDAP as the Private DRIP Identifier 5.2.2. EPP and RDAP as the Private DRIP Identifier
Registry . . . . . . . . . . . . . . . . . . . . . . 16 Registry . . . . . . . . . . . . . . . . . . . . . . 15
4.2.3. Alternative Private DRIP Registry methods . . . . . . 16 5.2.3. Alternative Private DRIP Registry methods . . . . . . 15
5. DRIP Identifier Trust . . . . . . . . . . . . . . . . . . . . 16 6. DRIP Identifier Trust . . . . . . . . . . . . . . . . . . . . 15
6. Harvesting Broadcast Remote ID messages for UTM Inclusion . . 17 7. Harvesting Broadcast Remote ID messages for UTM Inclusion . . 16
6.1. The CS-RID Finder . . . . . . . . . . . . . . . . . . . . 18 7.1. The CS-RID Finder . . . . . . . . . . . . . . . . . . . . 17
6.2. The CS-RID SDSP . . . . . . . . . . . . . . . . . . . . . 18 7.2. The CS-RID SDSP . . . . . . . . . . . . . . . . . . . . . 17
7. DRIP Contact . . . . . . . . . . . . . . . . . . . . . . . . 18 8. DRIP Contact . . . . . . . . . . . . . . . . . . . . . . . . 17
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18
9. Security Considerations . . . . . . . . . . . . . . . . . . . 19 10. Security Considerations . . . . . . . . . . . . . . . . . . . 18
10. Privacy & Transparency Considerations . . . . . . . . . . . . 19 11. Privacy & Transparency Considerations . . . . . . . . . . . . 18
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 19
11.1. Normative References . . . . . . . . . . . . . . . . . . 20 12.1. Normative References . . . . . . . . . . . . . . . . . . 19
11.2. Informative References . . . . . . . . . . . . . . . . . 20 12.2. Informative References . . . . . . . . . . . . . . . . . 19
Appendix A. Overview of Unmanned Aircraft Systems (UAS) Traffic Appendix A. Overview of Unmanned Aircraft Systems (UAS) Traffic
Management (UTM) . . . . . . . . . . . . . . . . . . . . 23 Management (UTM) . . . . . . . . . . . . . . . . . . . . 22
A.1. Operation Concept . . . . . . . . . . . . . . . . . . . . 23 A.1. Operation Concept . . . . . . . . . . . . . . . . . . . . 22
A.2. UAS Service Supplier (USS) . . . . . . . . . . . . . . . 24 A.2. UAS Service Supplier (USS) . . . . . . . . . . . . . . . 23
A.3. UTM Use Cases for UAS Operations . . . . . . . . . . . . 24 A.3. UTM Use Cases for UAS Operations . . . . . . . . . . . . 23
Appendix B. Automatic Dependent Surveillance Broadcast Appendix B. Automatic Dependent Surveillance Broadcast
(ADS-B) . . . . . . . . . . . . . . . . . . . . . . . . . 25 (ADS-B) . . . . . . . . . . . . . . . . . . . . . . . . . 24
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 25 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 24
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 25
1. Introduction 1. Introduction
This document describes an architecture for protocols and services to This document describes an architecture for protocols and services to
support Unmanned Aircraft System Remote Identification and tracking support Unmanned Aircraft System Remote Identification and tracking
(UAS RID), plus RID-related communications. The architecture takes (UAS RID), plus RID-related communications. The architecture takes
into account both current (including proposed) regulations and non- into account both current (including proposed) regulations and non-
IETF technical standards. IETF technical standards.
skipping to change at page 4, line 35 skipping to change at page 4, line 35
With release 16, the 3GPP completed the UAS RID requirement study With release 16, the 3GPP completed the UAS RID requirement study
[TS-22.825] and proposed a set of use cases in the mobile network [TS-22.825] and proposed a set of use cases in the mobile network
and the services that can be offered based on RID. Release 17 and the services that can be offered based on RID. Release 17
specification focuses on enhanced UAS service requirements and specification focuses on enhanced UAS service requirements and
provides the protocol and application architecture support that provides the protocol and application architecture support that
will be applicable for both 4G and 5G networks. The study of will be applicable for both 4G and 5G networks. The study of
Further Architecture Enhancement for Uncrewed Aerial Vehicles Further Architecture Enhancement for Uncrewed Aerial Vehicles
(UAV) and Urban Air Mobility (UAM) [FS_AEUA] in release 18 further (UAV) and Urban Air Mobility (UAM) [FS_AEUA] in release 18 further
enhances the communication mechanism between UAS and USS/UTM. The enhances the communication mechanism between UAS and USS/UTM. The
RID discussed in Section 3 may be used as the 3GPP CAA-level ID RID discussed in Section 4 may be used as the 3GPP CAA-level ID
for Remote Identification purposes. for Remote Identification purposes.
1.2. Overview of Types of UAS Remote ID 1.2. Overview of Types of UAS Remote ID
1.2.1. Broadcast RID 1.2.1. Broadcast RID
[F3411] defines a set of RID messages for direct, one-way, broadcast [F3411] defines a set of RID messages for direct, one-way, broadcast
transmissions from the UA over Bluetooth or Wi-Fi. These are transmissions from the UA over Bluetooth or Wi-Fi. These are
currently defined as MAC-Layer messages. Internet (or other Wide currently defined as MAC-Layer messages. Internet (or other Wide
Area Network) connectivity is only needed for UAS registry Area Network) connectivity is only needed for UAS registry
information lookup by Observers using the directly received UAS ID. information lookup by Observers using the directly received UAS ID.
Broadcast RID should be functionally usable in situations with no Broadcast RID should be functionally usable in situations with no
Internet connectivity. Internet connectivity.
The minimum Broadcast RID data flow is illustrated in Figure 1. The minimum Broadcast RID data flow is illustrated in Figure 1.
+------------------------+ +------------------------+
| Unmanned Aircraft (UA) | | Unmanned Aircraft (UA) |
+-----------o------------+ +-----------o------------+
| |
| |
| |
| app messages directly over | app messages directly over
| one-way RF data link (no IP) | one-way RF data link (no IP)
| |
| |
v v
+------------------o-------------------+ +------------------o-------------------+
| Observer's device (e.g., smartphone) | | Observer's device (e.g., smartphone) |
+--------------------------------------+ +--------------------------------------+
Figure 1 Figure 1
Broadcast RID provides information only about unmanned aircraft (UA) Broadcast RID provides information only about unmanned aircraft (UA)
within direct RF LOS, typically similar to visual Light-Of-Sight within direct RF LOS, typically similar to visual Light-Of-Sight
(LOS), with a range up to approximately 1 km. This information may (LOS), with a range up to approximately 1 km. This information may
be 'harvested' from received broadcasts and made available via the be 'harvested' from received broadcasts and made available via the
Internet, enabling surveillance of areas too large for local direct Internet, enabling surveillance of areas too large for local direct
visual observation or direct RF link based ID (see Section 6). visual observation or direct RF link based ID (see Section 7).
1.2.2. Network RID 1.2.2. Network RID
[F3411], using the same data dictionary that is the basis of [F3411], using the same data dictionary that is the basis of
Broadcast RID messages, defines a Network Remote Identification (Net- Broadcast RID messages, defines a Network Remote Identification (Net-
RID) data flow as follows. RID) data flow as follows.
* The information to be reported via RID is generated by the UAS * The information to be reported via RID is generated by the UAS
(typically some by the UA and some by the GCS, e.g. their (typically some by the UA and some by the GCS (Ground Control
respective GNSS derived locations). Station), e.g. their respective GNSS derived locations).
* The information is sent by the UAS (UA or GCS) via unspecified * The information is sent by the UAS (UA or GCS) via unspecified
means to the cognizant Network Remote Identification Service means to the cognizant Network Remote Identification Service
Provider (Net-RID SP), typically the USS under which the UAS is Provider (Net-RID SP), typically the USS under which the UAS is
operating if participating in UTM. operating if participating in UTM.
* The Net-RID SP publishes via the Discovery and Synchronization * The Net-RID SP publishes via the Discovery and Synchronization
Service (DSS) over the Internet that it has operations in various Service (DSS) over the Internet that it has operations in various
4-D airspace volumes, describing the volumes but not the 4-D airspace volumes, describing the volumes but not the
operations. operations.
skipping to change at page 6, line 15 skipping to change at page 6, line 15
* Using fully specified web based methods over the Internet, the * Using fully specified web based methods over the Internet, the
Net-RID DP queries all Net-RID SP that have operations in volumes Net-RID DP queries all Net-RID SP that have operations in volumes
intersecting that of the Observer's query for details on all such intersecting that of the Observer's query for details on all such
operations. operations.
* The Net-RID DP aggregates information received from all such Net- * The Net-RID DP aggregates information received from all such Net-
RID SP and responds to the Observer's query. RID SP and responds to the Observer's query.
The minimum Net-RID data flow is illustrated in Figure 2: The minimum Net-RID data flow is illustrated in Figure 2:
+-------------+ ****************** +-------------+ ******************
| UA | * Internet * | UA | * Internet *
+--o-------o--+ * * +--o-------o--+ * *
| | * * | | * *
| | * * +------------+ | | * * +------------+
| '--------*--(+)-----------*-----o | | '--------*--(+)-----------*-----o |
| * | * | | | * | * | |
| .--------*--(+)-----------*-----o NET-RID SP | | .--------*--(+)-----------*-----o Net-RID SP |
| | * * | | | | * * | |
| | * .------*-----o | | | * .------*-----o |
| | * | * +------------+ | | * | * +------------+
| | * | * | | * | *
| | * | * +------------+ | | * | * +------------+
| | * '------*-----o | | | * '------*-----o |
| | * * | NET-RID DP | | | * * | Net-RID DP |
| | * .------*-----o | | | * .------*-----o |
| | * | * +------------+ | | * | * +------------+
| | * | * | | * | *
| | * | * +------------+ | | * | * +------------+
+--o-------o--+ * '------*-----o Observer's | +--o-------o--+ * '------*-----o Observer's |
| GCS | * * | Device | | GCS | * * | Device |
+-------------+ ****************** +------------+ +-------------+ ****************** +------------+
Figure 2 Figure 2
Command and Control (C2) must flow from the GCS to the UA via some Command and Control (C2) must flow from the GCS to the UA via some
path, currently (in the year of 2021) typically a direct RF link, but path, currently (in the year of 2021) typically a direct RF link, but
with increasing beyond Visual Line of Sight (BVLOS) operations with increasing beyond Visual Line of Sight (BVLOS) operations, it is
expected often to be wireless links at either end with the Internet expected often to be wireless links at either end with the Internet
between. between.
Telemetry (at least UA's position and heading) flows from the UA to Telemetry (at least UA's position and heading) flows from the UA to
the GCS via some path, typically the reverse of the C2 path. Thus, the GCS via some path, typically the reverse of the C2 path. Thus,
RID information pertaining to both the GCS and the UA can be sent, by RID information pertaining to both the GCS and the UA can be sent, by
whichever has Internet connectivity, to the Net-RID SP, typically the whichever has Internet connectivity, to the Net-RID SP, typically the
USS managing the UAS operation. USS managing the UAS operation.
The Net-RID SP forwards RID information via the Internet to The Net-RID SP forwards RID information via the Internet to
subscribed Net-RID DP, typically USS. Subscribed Net-RID DP forward subscribed Net-RID DP, typically USS. Subscribed Net-RID DP forward
RID information via the Internet to subscribed Observer devices. RID information via the Internet to subscribed Observer devices.
Regulations require and [F3411] describes RID data elements that must Regulations require and [F3411] describes RID data elements that must
be transported end-to-end from the UAS to the subscribed Observer be transported end-to-end from the UAS to the subscribed Observer
devices. devices.
[F3411] prescribes the protocols between the Net-RID SP, Net-RID DP, [F3411] prescribes the protocols between the Net-RID SP, Net-RID DP,
and the Discovery and Synchronization Service (DSS). It also and the DSS. It also prescribes data elements (in JSON) between
prescribes data elements (in JSON) between Observer and Net-RID DP. Observer and Net-RID DP. DRIP could address standardization of
DRIP could address standardization of secure protocols between the UA secure protocols between the UA and GCS (over direct wireless and
and GCS (over direct wireless and Internet connection), between the Internet connection), between the UAS and the Net-RID SP, and/or
UAS and the Net-RID SP, and/or between the Net-RID DP and Observer between the Net-RID DP and Observer devices.
devices.
Informative note: Neither link layer protocols nor the use of Informative note: Neither link layer protocols nor the use of
links (e.g., the link often existing between the GCS and the links (e.g., the link often existing between the GCS and the
UA) for any purpose other than carriage of RID information is UA) for any purpose other than carriage of RID information is
in the scope of [F3411] Network RID. in the scope of [F3411] Network RID.
1.3. Overview of USS Interoperability 1.3. Overview of USS Interoperability
With Net-RID, there is direct communication between each UAS and its With Net-RID, there is direct communication between each UAS and its
USS. Multiple USS exchange information with the assistance of a USS. Multiple USS exchange information with the assistance of a DSS
Discovery and Synchronization Service (DSS) so all USS collectively so all USS collectively have knowledge about all activities in a 4D
have knowledge about all activities in a 4D airspace. airspace.
The interactions among an Observer, multiple UAS, and their USS are The interactions among an Observer, multiple UAS, and their USS are
shown in Figure 3. shown in Figure 3.
+------+ +----------+ +------+ +------+ +----------+ +------+
| UAS1 | | Observer | | UAS2 | | UAS1 | | Observer | | UAS2 |
+----o-+ +-----o----+ +-o----+ +----o-+ +-----o----+ +-o----+
| | | | | |
| | | | | |
******|*************|************|****** ******|*************|************|******
* | | | * * | | | *
* | +---o--+ | * * | +---o--+ | *
* | .------o USS3 o------. | * * | .------o USS3 o------. | *
* | | +--o---+ | | * * | | +--o---+ | | *
* | | | | | * * | | | | | *
* +-o--o-+ +--o--+ +-o--o-+ * * +-o--o-+ +--o--+ +-o--o-+ *
* | o----o DSS o-----o | * * | o----o DSS o-----o | *
* | USS1 | +-----+ | USS2 | * * | USS1 | +-----+ | USS2 | *
* | o----------------o | * * | o----------------o | *
* +------+ +------+ * * +------+ +------+ *
* * * *
* Internet * * Internet *
**************************************** ****************************************
Figure 3 Figure 3
1.4. Overview of DRIP Architecture 1.4. Overview of DRIP Architecture
Figure 4 illustrates the general UAS RID usage scenario. Broadcast Figure 4 illustrates the general UAS RID usage scenario. Broadcast
RID links are not shown as they reach from any UA to any listening RID links are not shown as they reach from any UA to any listening
receiver in range and thus would obscure the intent of the figure. receiver in range and thus would obscure the intent of the figure.
Figure 4 shows, as context, some entities and interfaces beyond the Figure 4 shows, as context, some entities and interfaces beyond the
scope of DRIP (as currently (2022) chartered). scope of DRIP (as currently (2022) chartered).
skipping to change at page 9, line 26 skipping to change at page 8, line 35
* | '-----*--------------* *--------------*-----' | * * | '-----*--------------* *--------------*-----' | *
* | * * * * | * * | * * * * | *
* | o====NetRID====* *====NetRID====o | * * | o====NetRID====* *====NetRID====o | *
* +--o--+ * * Internet * * +--o--+ * * +--o--+ * * Internet * * +--o--+ *
* | GCS o-----*--------------* *--------------*-----o GCS | * * | GCS o-----*--------------* *--------------*-----o GCS | *
* +-----+ * Registration * * Registration * +-----+ * * +-----+ * Registration * * Registration * +-----+ *
* * (and UTM) * * (and UTM) * * * * (and UTM) * * (and UTM) * *
*************** ************ *************** *************** ************ ***************
| | | | | |
+----------+ | | | +----------+ +----------+ | | | +----------+
| Public o---' | '---o Private | | Public o---' | '---o Private |
| Registry | | | Registry | | Registry | | | Registry |
+----------+ | +----------+ +----------+ | +----------+
+--o--+ +--o--+
| DNS | | DNS |
+-----+ +-----+
GPOD: General Public Observer Device (for brevity in this figure) GPOD: General Public Observer Device (for brevity in this figure)
PSOD: Public Safety Observer Device (for brevity in this figure) PSOD: Public Safety Observer Device (for brevity in this figure)
Figure 4 Figure 4
skipping to change at page 9, line 50 skipping to change at page 9, line 11
UAS RID and closely related needs. DRIP will specify how to apply UAS RID and closely related needs. DRIP will specify how to apply
IETF standards, complementing [F3411] and other external standards, IETF standards, complementing [F3411] and other external standards,
to satisfy UAS RID requirements. to satisfy UAS RID requirements.
This document outlines the DRIP architecture in the context of the This document outlines the DRIP architecture in the context of the
UAS RID architecture. This includes presenting the gaps between the UAS RID architecture. This includes presenting the gaps between the
CAAs' Concepts of Operations and [F3411] as it relates to the use of CAAs' Concepts of Operations and [F3411] as it relates to the use of
Internet technologies and UA direct RF communications. Issues Internet technologies and UA direct RF communications. Issues
include, but are not limited to: include, but are not limited to:
o Design of trustworthy remote identifiers (Section 3). - Design of trustworthy remote identifiers (Section 4).
- Mechanisms to leverage Domain Name System (DNS [RFC1034]), - Mechanisms to leverage Domain Name System (DNS [RFC1034]),
Extensible Provisioning Protocol (EPP [RFC5731]) and Extensible Provisioning Protocol (EPP [RFC5731]) and
Registration Data Access Protocol (RDAP) ([RFC7482]) for Registration Data Access Protocol (RDAP) ([RFC9082]) for
publishing public and private information (see Section 4.1 and publishing public and private information (see Section 5.1 and
Section 4.2). Section 5.2).
- Specific authentication methods and message payload formats to - Specific authentication methods and message payload formats to
enable verification that Broadcast RID messages were sent by enable verification that Broadcast RID messages were sent by
the claimed sender (Section 5) and that sender is in the the claimed sender (Section 6) and that sender is in the
claimed registry (Section 4 and Section 5). claimed registry (Section 5 and Section 6).
- Harvesting broadcast RID messages for UTM inclusion - Harvesting broadcast RID messages for UTM inclusion
(Section 6). (Section 7).
- Methods for instantly establishing secure communications - Methods for instantly establishing secure communications
between an Observer and the pilot of an observed UAS between an Observer and the pilot of an observed UAS
(Section 7). (Section 8).
- Privacy in RID messages (PII protection) (Section 10).
2. Terms and Definitions - Privacy in RID messages (PII protection) (Section 11).
2.1. Architecture Terminology 2. Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown above. capitals, as shown here.
2.2. Abbreviations 3. Terms and Definitions
3.1. Abbreviations
EdDSA: Edwards-Curve Digital Signature Algorithm EdDSA: Edwards-Curve Digital Signature Algorithm
HHIT: Hierarchical HIT HHIT: Hierarchical HIT
HIP: Host Identity Protocol HIP: Host Identity Protocol
HIT: Host Identity Tag HIT: Host Identity Tag
2.3. Claims, Assertions, Attestations, and Certificates 3.2. Claims, Assertions, Attestations, and Certificates
This section introduces the terms "Claims", "Assertions", This section introduces the terms "Claims", "Assertions",
"Attestations", and "Certificates" as used in DRIP. DRIP certificate "Attestations", and "Certificates" as used in DRIP. DRIP certificate
has a different context compared with security certificates and has a different context compared with security certificates and
Public Key Infrastructure used in X.509. Public Key Infrastructure used in X.509.
Claims: Claims:
A claim in DRIP is a predicate (e.g., "X is Y", "X has property A claim in DRIP is a predicate (e.g., "X is Y", "X has property
Y", and most importantly "X owns Y" or "X is owned by Y"). Y", and most importantly "X owns Y" or "X is owned by Y").
skipping to change at page 11, line 28 skipping to change at page 10, line 37
relationship with another entity, along with other information, relationship with another entity, along with other information,
and the asserting entity signs the assertion, thereby making it an and the asserting entity signs the assertion, thereby making it an
attestation. attestation.
Certificates: Certificates:
A certificate in DRIP is an attestation, strictly over identity A certificate in DRIP is an attestation, strictly over identity
information, signed by a third party. This third party should be information, signed by a third party. This third party should be
one with no stake in the attestation(s) its signing over. one with no stake in the attestation(s) its signing over.
2.4. Additional Definitions 3.3. Additional Definitions
This document uses terms defined in [I-D.ietf-drip-reqs]. This document uses terms defined in [I-D.ietf-drip-reqs].
3. HHIT as the DRIP Entity Identifier 4. HHIT as the DRIP Entity Identifier
This section describes the DRIP architectural approach to meeting the This section describes the DRIP architectural approach to meeting the
basic requirements of a DRIP entity identifier within external basic requirements of a DRIP entity identifier within external
technical standard ASTM [F3411] and regulatory constraints. It technical standard ASTM [F3411] and regulatory constraints. It
justifies and explains the use of Hierarchical Host Identity Tags justifies and explains the use of Hierarchical Host Identity Tags
(HHITs) as self-asserting IPv6 addresses suitable as a UAS ID type (HHITs) as self-asserting IPv6 addresses suitable as a UAS ID type
and more generally as trustworthy multipurpose remote identifiers. and more generally as trustworthy multipurpose remote identifiers.
Self-asserting in this usage is given the Host Identity (HI), the Self-asserting in this usage is given by the Host Identity (HI), the
HHIT ORCHID construction and a signature of the HHIT by the HI can HHIT ORCHID construction and a signature of the HHIT by the HI can
both be validated. The explicit registration hierarchy within the both be validated. The explicit registration hierarchy within the
HHIT provides registry discovery (managed by a Registrar) to either HHIT provides registry discovery (managed by a Registrar) to either
yield the HI for 3rd-party (who is looking for ID attestation) yield the HI for 3rd-party (who is looking for ID attestation)
validation or prove the HHIT and HI have uniquely been registered. validation or prove the HHIT and HI have uniquely been registered.
3.1. UAS Remote Identifiers Problem Space 4.1. UAS Remote Identifiers Problem Space
A DRIP entity identifier needs to be "Trustworthy" (See DRIP A DRIP entity identifier needs to be "Trustworthy" (See DRIP
Requirement GEN-1, ID-4 and ID-5 in [I-D.ietf-drip-reqs]). This Requirement GEN-1, ID-4 and ID-5 in [I-D.ietf-drip-reqs]). This
means that given a sufficient collection of RID messages, an Observer means that given a sufficient collection of RID messages, an Observer
can establish that the identifier claimed therein uniquely belongs to can establish that the identifier claimed therein uniquely belongs to
the claimant: that the only way for any other entity to prove the claimant. To satisfy DRIP requirements and maintain important
ownership of that identifier would be to obtain information that security properties, the DRIP identifier should be self-generated by
ought to be available only to the legitimate owner of the identifier the entity it names (e.g., a UAS) and registered (e.g., with a USS,
(e.g., a cryptographic private key). see Requirements GEN-3 and ID-2).
To satisfy DRIP requirements and maintain important security
properties, the DRIP identifier should be self-generated by the
entity it names (e.g., a UAS) and registered (e.g., with a USS, see
Requirements GEN-3 and ID-2).
Broadcast RID, especially its support for Bluetooth 4, imposes severe Broadcast RID, especially its support for Bluetooth 4, imposes severe
constraints. ASTM RID [F3411] allows a UAS ID of types 1, 2 and 3 of constraints. ASTM RID [F3411] allows a UAS ID of types 1, 2 and 3 of
20 bytes; a revision to [F3411], currently in balloting (as of Oct 20 bytes; a revision to [F3411], currently in balloting (as of Oct
2021), adds type 4, Session IDs, to be standardized by IETF and other 2021), adds type 4, Session IDs, to be standardized by IETF and other
standard development organizations (SDOs) as extensions to ASTM RID, standard development organizations (SDOs) as extensions to ASTM RID,
consumes one of those bytes to index the sub-type, leaving only 19 consumes one of those bytes to index the sub-type, leaving only 19
for the identifier (see DRIP Requirement ID-1). Likewise, the for the identifier (see DRIP Requirement ID-1).
maximum ASTM RID [F3411] Authentication Message payload is 201 bytes
for most authentication types, but for type 5, also added in this
revision, for IETF and other SDOs to develop Specific Authentication
Methods as extensions to ASTM RID, one byte is consumed to index the
sub-type, leaving only 200 for DRIP authentication payloads,
including one or more DRIP entity identifiers and associated
authentication data.
3.2. HHIT as A Trustworthy DRIP Entity Identifier Likewise, the maximum ASTM RID [F3411] Authentication Message payload
is 201 bytes for most authentication types, but for type 5, also
added in this revision, for IETF and other SDOs to develop Specific
Authentication Methods as extensions to ASTM RID, one byte is
consumed to index the sub-type, leaving only 200 for DRIP
authentication payloads, including one or more DRIP entity
identifiers and associated authentication data.
4.2. HHIT as A Trustworthy DRIP Entity Identifier
A Remote ID that can be trustworthily used in the RID Broadcast mode A Remote ID that can be trustworthily used in the RID Broadcast mode
can be built from an asymmetric keypair. Rather than using a key can be built from an asymmetric keypair. In this method the ID is
signing operation to claim ownership of an ID that does not guarantee cryptographically derived directly from the public key. The proof of
name uniqueness, in this method the ID is cryptographically derived ID ownership (verifiable attestation, versus mere claim) is
directly from the public key. The proof of ID ownership (verifiable guaranteed by signing this cryptographic ID with the associated
attestation, versus mere claim) is guaranteed by signing this private key. The association between the ID and the private key is
cryptographic ID with the associated private key. The association ensured by cryptographically binding the public key with the ID, more
between the ID and the private key is ensured by cryptographically specifically the ID results from the hash of the public key. The
binding the public key with the ID, more specifically the ID results public key is designated as the HI while the ID is designated as the
from the hash of the public key. It is statistically hard for HIT.
another entity to create a public key that would generate (spoof) the
ID.
The basic HIT is designed statistically unique through the By construction, the HIT is statistically unique through the
cryptographic hash feature of second-preimage resistance. The cryptographic hash feature of second-preimage resistance. The
cryptographically-bound addition of the Hierarchy and an HHIT cryptographically-bound addition of the Hierarchy and an HHIT
registration process (e.g. based on Extensible Provisioning Protocol, registration process provide complete, global HHIT uniqueness. This
[RFC5730]) provide complete, global HHIT uniqueness. This
registration forces the attacker to generate the same public key registration forces the attacker to generate the same public key
rather than a public key that generates the same HHIT. This is in rather than a public key that generates the same HHIT. This is in
contrast to general IDs (e.g. a UUID or device serial number) as the contrast to general IDs (e.g. a UUID or device serial number) as the
subject in an X.509 certificate. subject in an X.509 certificate.
A DRIP identifier can be assigned to a UAS as a static HHIT by its
manufacturer, such as a single HI and derived HHIT encoded as a
hardware serial number per [CTA2063A]. Such a static HHIT SHOULD
only be used to bind one-time use DRIP identifiers to the unique UA.
Depending upon implementation, this may leave a HI private key in the
possession of the manufacturer (more details in Section 9).
A UA equipped for Broadcast RID SHOULD be provisioned not only with A UA equipped for Broadcast RID SHOULD be provisioned not only with
its HHIT but also with the HI public key from which the HHIT was its HHIT but also with the HI public key from which the HHIT was
derived and the corresponding private key, to enable message derived and the corresponding private key, to enable message
signature. A UAS equipped for Network RID SHOULD be provisioned signature. A UAS equipped for Network RID SHOULD be provisioned
likewise; the private key resides only in the ultimate source of likewise; the private key resides only in the ultimate source of
Network RID messages (i.e. on the UA itself if the GCS is merely Network RID messages (i.e. on the UA itself if the GCS is merely
relaying rather than sourcing Network RID messages). Each Observer relaying rather than sourcing Network RID messages). Each Observer
device SHOULD be provisioned either with public keys of the DRIP device SHOULD be provisioned either with public keys of the DRIP
identifier root registries or certificates for subordinate identifier root registries or certificates for subordinate
registries. registries.
HHITs can also be used throughout the USS/UTM system. The Operators, HHITs can also be used throughout the USS/UTM system. The Operators,
Private Information Registries, as well as other UTM entities, can Private Information Registries, as well as other UTM entities, can
use HHITs for their IDs. Such HHITs can facilitate DRIP security use HHITs for their IDs. Such HHITs can facilitate DRIP security
functions such as used with HIP to strongly mutually authenticate and functions such as used with HIP to strongly mutually authenticate and
encrypt communications. encrypt communications.
A self-attestation of a HHIT used as a UAS ID can be done in as A self-attestation of a HHIT used as a UAS ID can be done in as
little as 84 bytes, by avoiding an explicit encoding technology like little as 84 bytes when Ed25519 [RFC8032] is used, by avoiding an
ASN.1 or Concise Binary Object Representation (CBOR [RFC8949]). This explicit encoding technology like ASN.1 or Concise Binary Object
attestation consists of only the HHIT, a timestamp, and the EdDSA Representation (CBOR [RFC8949]). This attestation consists of only
signature on them. the HHIT, a timestamp, and the EdDSA signature on them.
A DRIP identifier can be assigned to a UAS as a static HHIT by its
manufacturer, such as a single HI and derived HHIT encoded as a
hardware serial number per [CTA2063A]. Such a static HHIT SHOULD
only be used to bind one-time use DRIP identifiers to the unique UA.
Depending upon implementation, this may leave a HI private key in the
possession of the manufacturer (more details in Section 10).
In general, Internet access may be needed to validate Attestations or In general, Internet access may be needed to validate Attestations or
Certificates. This may be obviated in the most common cases (e.g. Certificates. This may be obviated in the most common cases (e.g.
attestation of the UAS ID), even in disconnected environments, by attestation of the UAS ID), even in disconnected environments, by
prepopulating small caches on Observer devices with Registry public prepopulating small caches on Observer devices with Registry public
keys and a chain of Attestations or Certificates (tracing a path keys and a chain of Attestations or Certificates (tracing a path
through the Registry tree). This is assuming all parties on the through the Registry tree). This is assuming all parties on the
trust path also use HHITs for their identities. trust path also use HHITs for their identities.
3.3. HHIT for DRIP Identifier Registration and Lookup 4.3. HHIT for DRIP Identifier Registration and Lookup
Remote ID needs a deterministic lookup mechanism that rapidly RID needs a deterministic lookup mechanism that rapidly provides
provides actionable information about the identified UA. Given the actionable information about the identified UA. Given the size
size constraints imposed by the Bluetooth 4 broadcast media, the UAS constraints imposed by the Bluetooth 4 broadcast media, the UAS ID
ID itself needs to be a non-spoofable inquiry input into the lookup. itself needs to be a non-spoofable inquiry input into the lookup.
A DRIP registration process based on the explicit hierarchy within a A DRIP registration process based on the explicit hierarchy within a
HHIT provides manageable uniqueness of the HI for the HHIT. This is HHIT provides manageable uniqueness of the HI for the HHIT. This is
the defense against a cryptographic hash second pre-image attack on the defense against a cryptographic hash second pre-image attack on
the HHIT (e.g. multiple HIs yielding the same HHIT, see Requirement the HHIT (e.g. multiple HIs yielding the same HHIT, see Requirement
ID-3). A lookup of the HHIT into this registration data provides the ID-3). A lookup of the HHIT into this registration data provides the
registered HI for HHIT proof. A first-come-first-serve registration registered HI for HHIT proof of ownership. A first-come-first-serve
for a HHIT provides deterministic access to any other needed registration for a HHIT provides deterministic access to any other
actionable information based on inquiry access authority (more needed actionable information based on inquiry access authority (more
details in Section 4.2). details in Section 5.2).
3.4. HHIT as a Cryptographic Identifier 4.4. HHIT as a Cryptographic Identifier
The only (known to the authors at the time of this writing) extant The only (known to the authors at the time of this writing) extant
types of IP address compatible identifiers cryptographically derived types of IP address compatible identifiers cryptographically derived
from the public keys of the identified entities are Cryptographically from the public keys of the identified entities are Cryptographically
Generated Addresses (CGAs) [RFC3972] and Host Identity Tags (HITs) Generated Addresses (CGAs) [RFC3972] and Host Identity Tags (HITs)
[RFC7401]. CGAs and HITs lack registration/retrieval capability. To [RFC7401]. CGAs and HITs lack registration/retrieval capability. To
provide this, each HHIT embeds plaintext information designating the provide this, each HHIT embeds plaintext information designating the
hierarchy within which is registered and a cryptographic hash of that hierarchy within which it is registered and a cryptographic hash of
information concatenated with the entity's public key, etc. Although that information concatenated with the entity's public key, etc.
hash collisions may occur, the registrar can detect them and reject Although hash collisions may occur, the registrar can detect them and
registration requests rather than issue credentials, e.g., by reject registration requests rather than issue credentials, e.g., by
enforcing a first-claimed, first-attested policy. Pre-image hash enforcing a first-claimed, first-attested policy. Pre-image hash
attacks are also mitigated through this registration process, locking attacks are also mitigated through this registration process, locking
the HHIT to a specific HI the HHIT to a specific HI
4. DRIP Identifier Registration and Registries 5. DRIP Identifier Registration and Registries
DRIP registries hold both public and private UAS information DRIP registries hold both public and private UAS information
resulting from the DRIP identifier registration process. Given these resulting from the DRIP identifier registration process. Given these
different uses, and to improve scalability, security, and simplicity different uses, and to improve scalability, security, and simplicity
of administration, the public and private information can be stored of administration, the public and private information can be stored
in different registries. This section introduces the public and in different registries. This section introduces the public and
private information registries for DRIP identifiers. This DRIP private information registries for DRIP identifiers. This DRIP
Identifier registration process satisfies the following DRIP Identifier registration process satisfies the following DRIP
requirements defined in [I-D.ietf-drip-reqs]: GEN-3, GEN-4, ID-2, ID- requirements defined in [I-D.ietf-drip-reqs]: GEN-3, GEN-4, ID-2, ID-
4, ID-6, PRIV-3, PRIV-4, REG-1, PRG-2, REG-3 and REG-4. 4, ID-6, PRIV-3, PRIV-4, REG-1, PRG-2, REG-3 and REG-4.
4.1. Public Information Registry 5.1. Public Information Registry
4.1.1. Background 5.1.1. Background
The public registry provides trustable information such as The public registry provides trustable information such as
attestations of RID ownership and registration with the HDA attestations of RID ownership and registration with the HDA
(Hierarchical HIT Domain Authority). Optionally, pointers to the (Hierarchical HIT Domain Authority). Optionally, pointers to the
registries for the HDA and RAA (Registered Assigning registries for the HDA and RAA (Registered Assigning
Authority)implicit in the RID can be included (e.g., for HDA and RAA Authority)implicit in the RID can be included (e.g., for HDA and RAA
HHIT|HI used in attestation signing operations). This public HHIT|HI used in attestation signing operations). This public
information will be principally used by Observers of Broadcast RID information will be principally used by Observers of Broadcast RID
messages. Data on UAS that only use Network RID, is available via an messages. Data on UAS that only use Network RID, is available via an
Observer's Net-RID DP that would tend to directly provide all public Observer's Net-RID DP that would tend to directly provide all public
registry information. The Observer may visually "see" these Net-RID registry information. The Observer may visually "see" these Net-RID
UAS, but they may be silent to the Observer. The Net-RID DP is the UAS, but they may be silent to the Observer. The Net-RID DP is the
only source of information based on a query for an airspace volume. only source of information based on a query for an airspace volume.
4.1.2. DNS as the Public DRIP Identifier Registry 5.1.2. DNS as the Public DRIP Identifier Registry
A DRIP identifier SHOULD be registered as an Internet domain name (at A DRIP identifier SHOULD be registered as an Internet domain name (at
an arbitrary level in the hierarchy, e.g. in .ip6.arpa). Thus DNS an arbitrary level in the hierarchy, e.g. in .ip6.arpa). Thus DNS
can provide all the needed public DRIP information. A standardized can provide all the needed public DRIP information. A standardized
HHIT FQDN (Fully Qualified Domain Name) can deliver the HI via a HIP HHIT FQDN (Fully Qualified Domain Name) can deliver the HI via a HIP
RR (Resource Record) [RFC8005] and other public information (e.g., RR (Resource Record) [RFC8005] and other public information (e.g.,
RRA and HDA PTRs, and HIP RVS (Rendezvous Servers) [RFC8004]). These RRA and HDA PTRs, and HIP RVS (Rendezvous Servers) [RFC8004]). These
public information registries can use secure DNS transport (e.g. DNS public information registries can use secure DNS transport (e.g. DNS
over TLS) to deliver public information that is not inherently over TLS) to deliver public information that is not inherently
trustable (e.g. everything other than attestations). trustable (e.g. everything other than attestations).
4.2. Private Information Registry 5.2. Private Information Registry
4.2.1. Background 5.2.1. Background
The private information required for DRIP identifiers is similar to The private information required for DRIP identifiers is similar to
that required for Internet domain name registration. A DRIP that required for Internet domain name registration. A DRIP
identifier solution can leverage existing Internet resources: identifier solution can leverage existing Internet resources:
registration protocols, infrastructure, and business models, by registration protocols, infrastructure, and business models, by
fitting into an ID structure compatible with DNS names. The HHIT fitting into an ID structure compatible with DNS names. The HHIT
hierarchy can provide the needed scalability and management hierarchy can provide the needed scalability and management
structure. It is expected that the private registry function will be structure. It is expected that the private registry function will be
provided by the same organizations that run a USS, and likely provided by the same organizations that run a USS, and likely
integrated with a USS. The lookup function may be implemented by the integrated with a USS. The lookup function may be implemented by the
Net-RID DPs. Net-RID DPs.
4.2.2. EPP and RDAP as the Private DRIP Identifier Registry 5.2.2. EPP and RDAP as the Private DRIP Identifier Registry
A DRIP private information registry supports essential registry A DRIP private information registry supports essential registry
operations (e.g. add, delete, update, query) using interoperable open operations (e.g. add, delete, update, query) using interoperable open
standard protocols. It can accomplish this by using the Extensible standard protocols. It can accomplish this by using the Extensible
Provisioning Protocol (EPP [RFC5730]) and the Registry Data Access Provisioning Protocol (EPP [RFC5730]) and the Registry Data Access
Protocol (RDAP RFC7480] [RFC7482] [RFC7483]). The DRIP private Protocol (RDAP RFC7480] [RFC9082] [RFC9083]). The DRIP private
information registry in which a given UAS is registered needs to be information registry in which a given UAS is registered needs to be
findable, starting from the UAS ID, using the methods specified in findable, starting from the UAS ID, using the methods specified in
[RFC7484]. [RFC7484].
4.2.3. Alternative Private DRIP Registry methods 5.2.3. Alternative Private DRIP Registry methods
A DRIP private information registry might be an access controlled DNS A DRIP private information registry might be an access controlled DNS
(e.g. via DNS over TLS). Additionally, WebFinger [RFC7033] can be (e.g. via DNS over TLS). Additionally, WebFinger [RFC7033] can be
deployed. These alternative methods may be used by Net-RID DP with deployed. These alternative methods may be used by Net-RID DP with
specific customers. specific customers.
5. DRIP Identifier Trust 6. DRIP Identifier Trust
While the DRIP entity identifier is self-asserting, it alone does not While the DRIP entity identifier is self-asserting, it alone does not
provide the "trustworthiness" specified in [I-D.ietf-drip-reqs]. For provide the "trustworthiness" specified in [I-D.ietf-drip-reqs]. For
that it MUST be registered (under DRIP Registries) and be actively that it MUST be registered (under DRIP Registries) and be actively
used by the party (in most cases the UA). For Broadcast RID this is used by the party (in most cases the UA). For example, when a sender
a challenge to balance the original requirements of Broadcast RID and simply possessing a DET (DRIP Entity Tag which is a HHIT-based UAS
the efforts needed to satisfy the DRIP requirements all under severe ID) and broadcasting a claim that it belongs to that sender proves
constraints. nothing about that sender's identity. Even the sender using that
HI's private key to sign static data proves nothing as well, as it is
subject to trivial replay attacks. Only sending the DET and a
signature on frequently changing data that can be sanity checked by
the Observer (such as a Location/Vector message) proves that the
observed UA possesses the claimed UAS ID.
From received Broadcast RID messages and information that can be For Broadcast RID, this is a challenge to balance the original
looked up using the received UAS ID in online registries or local requirements of Broadcast RID and the efforts needed to satisfy the
caches, it is possible to establish levels of trust in the asserted DRIP requirements all under severe constraints. From received
information and the Operator. Broadcast RID messages and information that can be looked up using
the received UAS ID in online registries or local caches, it is
possible to establish levels of trust in the asserted information and
the Operator.
An optimization of different DRIP Authentication Messages allows an An optimization of different DRIP Authentication Messages allows an
Observer, without Internet connection (offline) or with (online), to Observer, without Internet connection (offline) or with (online), to
be able to validate a UAS DRIP ID in real-time. First is the sending be able to validate a UAS DRIP ID in real-time. First is the sending
of Broadcast Attestations (over DRIP Link Authentication Messages) of Broadcast Attestations (over DRIP Link Authentication Messages)
containing the relevant registration of the UA's DRIP ID in the [I-D.ietf-drip-auth] containing the relevant registration of the UA's
claimed Registry. Next is sending DRIP Wrapper Authentication DRIP ID in the claimed Registry. Next is sending DRIP Wrapper
Messages that sign over both static (e.g. above registration) and Authentication Messages that sign over both static (e.g. above
dynamically changing data (such as UA location data). Combining registration) and dynamically changing data (such as UA location
these two sets of information an Observer can piece together a chain data). Combining these two sets of information an Observer can piece
of trust and real-time evidence to make their determination of the together a chain of trust and real-time evidence to make their
UAs claims. determination of the UAs claims.
This process (combining the DRIP entity identifier, Registries and This process (combining the DRIP entity identifier, Registries and
Authentication Formats for Broadcast RID) can satisfy the following Authentication Formats for Broadcast RID) can satisfy the following
DRIP requirement defined in [I-D.ietf-drip-reqs]: GEN-1, GEN-2, GEN- DRIP requirement defined in [I-D.ietf-drip-reqs]: GEN-1, GEN-2, GEN-
3, ID-2, ID-3, ID-4 and ID-5. 3, ID-2, ID-3, ID-4 and ID-5.
6. Harvesting Broadcast Remote ID messages for UTM Inclusion 7. Harvesting Broadcast Remote ID messages for UTM Inclusion
ASTM anticipated that regulators would require both Broadcast RID and ASTM anticipated that regulators would require both Broadcast RID and
Network RID for large UAS, but allow RID requirements for small UAS Network RID for large UAS, but allow RID requirements for small UAS
to be satisfied with the operator's choice of either Broadcast RID or to be satisfied with the operator's choice of either Broadcast RID or
Network RID. The EASA initially specified Broadcast RID for UAS of Network RID. The EASA initially specified Broadcast RID for UAS of
essentially all UAS and is now also considering Network RID. The FAA essentially all UAS and is now also considering Network RID. The FAA
RID Final Rules [FAA_RID] permit only Broadcast RID for rule RID Final Rules [FAA_RID] permit only Broadcast RID for rule
compliance, but still encourage Network RID for complementary compliance, but still encourage Network RID for complementary
functionality, especially in support of UTM. functionality, especially in support of UTM.
skipping to change at page 18, line 5 skipping to change at page 17, line 8
Further, gateways with additional sensors (e.g. smartphones with Further, gateways with additional sensors (e.g. smartphones with
cameras) can provide independent information on the UA type and size, cameras) can provide independent information on the UA type and size,
confirming or refuting those claims made in the RID messages. This confirming or refuting those claims made in the RID messages. This
Crowd Sourced Remote ID (CS-RID) would be a significant enhancement, Crowd Sourced Remote ID (CS-RID) would be a significant enhancement,
beyond baseline DRIP functionality; if implemented, it adds two more beyond baseline DRIP functionality; if implemented, it adds two more
entity types. entity types.
This approach satisfies the following DRIP requirements defined in This approach satisfies the following DRIP requirements defined in
[I-D.ietf-drip-reqs]: GEN-5, GEN-11, and REG-1. [I-D.ietf-drip-reqs]: GEN-5, GEN-11, and REG-1.
6.1. The CS-RID Finder 7.1. The CS-RID Finder
A CS-RID Finder is the gateway for Broadcast Remote ID Messages into A CS-RID Finder is the gateway for Broadcast Remote ID Messages into
the UTM. It performs this gateway function via a CS-RID SDSP. A CS- the UTM. It performs this gateway function via a CS-RID SDSP. A CS-
RID Finder could implement, integrate, or accept outputs from, a RID Finder could implement, integrate, or accept outputs from, a
Broadcast RID receiver. However, it should not depend upon a direct Broadcast RID receiver. However, it should not depend upon a direct
interface with a GCS, Net-RID SP, Net-RID DP or Network RID client. interface with a GCS, Net-RID SP, Net-RID DP or Network RID client.
It would present a TBD interface to a CS-RID SDSP, similar to but It would present a TBD interface to a CS-RID SDSP, similar to but
readily distinguishable from that between a GCS and a Net-RID SP. readily distinguishable from that between a GCS and a Net-RID SP.
6.2. The CS-RID SDSP 7.2. The CS-RID SDSP
A CS-RID SDSP aggregates and processes (e.g., estimates UA location A CS-RID SDSP aggregates and processes (e.g., estimates UA location
using including using multilateration when possible) information using including using multilateration when possible) information
collected by CS-RID Finders. A CS-RID SDSP should appear (i.e. collected by CS-RID Finders. A CS-RID SDSP should appear (i.e.
present the same interface) to a Net-RID SP as a Net-RID DP. present the same interface) to a Net-RID SP as a Net-RID DP.
7. DRIP Contact 8. DRIP Contact
One of the ways in which DRIP can enhance [F3411] with immediately One of the ways in which DRIP can enhance [F3411] with immediately
actionable information is by enabling an Observer to instantly actionable information is by enabling an Observer to instantly
initiate secure communications with the UAS remote pilot, Pilot In initiate secure communications with the UAS remote pilot, Pilot In
Command, operator, USS under which the operation is being flown, or Command, operator, USS under which the operation is being flown, or
other entity potentially able to furnish further information other entity potentially able to furnish further information
regarding the operation and its intent and/or to immediately regarding the operation and its intent and/or to immediately
influence further conduct or termination of the operation (e.g., land influence further conduct or termination of the operation (e.g., land
or otherwise exit an airspace volume). Such potentially distracting or otherwise exit an airspace volume). Such potentially distracting
communications demand strong "AAA" (Authentication, Attestation, communications demand strong "AAA" (Authentication, Attestation,
Authorization, Access Control, Accounting, Attribution, Audit) per Authorization, Access Control, Accounting, Attribution, Audit) per
applicable policies (e.g., of the cognizant CAA). applicable policies (e.g., of the cognizant CAA).
A DRIP entity identifier based on a HHIT as outlined in Section 3 A DRIP entity identifier based on a HHIT as outlined in Section 4
embeds an identifier of the registry in which it can be found embeds an identifier of the registry in which it can be found
(expected typically to be the USS under which the UAS is flying) and (expected typically to be the USS under which the UAS is flying) and
the procedures outlined in Section 5 enable Observer verification of the procedures outlined in Section 6 enable Observer verification of
that relationship. A DRIP entity identifier with suitable records in that relationship. A DRIP entity identifier with suitable records in
public and private registries as outlined in Section 5 can enable public and private registries as outlined in Section 5 can enable
lookup not only of information regarding the UAS but also identities lookup not only of information regarding the UAS but also identities
of and pointers to information regarding the various associated of and pointers to information regarding the various associated
entities (e.g., the USS under which the UAS is flying an operation), entities (e.g., the USS under which the UAS is flying an operation),
including means of contacting those associated entities (i.e., including means of contacting those associated entities (i.e.,
locators, typically IP addresses). An Observer equipped with HIP can locators, typically IP addresses). An Observer equipped with HIP can
initiate a Base Exchange (BEX) and establish a Bound End to End initiate a Base Exchange (BEX) and establish a Bound End to End
Tunnel (BEET) protected by IPsec Encapsulating Security Payload (ESP) Tunnel (BEET) protected by IPsec Encapsulating Security Payload (ESP)
encryption to a likewise equipped and identified entity: the UA encryption to a likewise equipped and identified entity: the UA
skipping to change at page 19, line 16 skipping to change at page 18, line 19
currently usable locator (IP address); and there must be currently currently usable locator (IP address); and there must be currently
usable bidirectional IP (not necessarily Internet) connectivity usable bidirectional IP (not necessarily Internet) connectivity
between the parties. Given a BEET, arbitrary standard higher layer between the parties. Given a BEET, arbitrary standard higher layer
protocols can then be used for Observer to Pilot (O2P) communications protocols can then be used for Observer to Pilot (O2P) communications
(e.g., SIP [RFC3261] et seq), V2X communications (e.g., [MAVLink]), (e.g., SIP [RFC3261] et seq), V2X communications (e.g., [MAVLink]),
etc. This approach satisfies DRIP requirement GEN-6 Contact, etc. This approach satisfies DRIP requirement GEN-6 Contact,
supports satisfaction of requirements [I-D.ietf-drip-reqs] GEN-8, supports satisfaction of requirements [I-D.ietf-drip-reqs] GEN-8,
GEN-9, PRIV-2, PRIV-5 and REG-3, and is compatible with all other GEN-9, PRIV-2, PRIV-5 and REG-3, and is compatible with all other
DRIP requirements. DRIP requirements.
8. IANA Considerations 9. IANA Considerations
This document does not make any IANA request. This document does not make any IANA request.
9. Security Considerations 10. Security Considerations
The security provided by asymmetric cryptographic techniques depends The security provided by asymmetric cryptographic techniques depends
upon protection of the private keys. A manufacturer that embeds a upon protection of the private keys. A manufacturer that embeds a
private key in an UA may have retained a copy. A manufacturer whose private key in an UA may have retained a copy. A manufacturer whose
UA are configured by a closed source application on the GCS which UA are configured by a closed source application on the GCS which
communicates over the Internet with the factory may be sending a copy communicates over the Internet with the factory may be sending a copy
of a UA or GCS self-generated key back to the factory. Keys may be of a UA or GCS self-generated key back to the factory. Keys may be
extracted from a GCS or UA. The RID sender of a small harmless UA extracted from a GCS or UA. The RID sender of a small harmless UA
(or the entire UA) could be carried by a larger dangerous UA as a (or the entire UA) could be carried by a larger dangerous UA as a
"false flag." Compromise of a registry private key could do "false flag." Compromise of a registry private key could do
widespread harm. Key revocation procedures are as yet to be widespread harm. Key revocation procedures are as yet to be
determined. These risks are in addition to those involving Operator determined. These risks are in addition to those involving Operator
key management practices. key management practices.
10. Privacy & Transparency Considerations 11. Privacy & Transparency Considerations
Broadcast RID messages can contain Personally Identifiable Broadcast RID messages can contain Personally Identifiable
Information (PII). A viable architecture for PII protection would be Information (PII). A viable architecture for PII protection would be
symmetric encryption of the PII using a session key known to the UAS symmetric encryption of the PII using a session key known to the UAS
and its USS. Authorized Observers could obtain plaintext in either and its USS. Authorized Observers could obtain plaintext in either
of two ways. An Observer can send the UAS ID and the cyphertext to a of two ways. An Observer can send the UAS ID and the cyphertext to a
server that offers decryption as a service. An Observer can send the server that offers decryption as a service. An Observer can send the
UAS ID only to a server that returns the session key, so that UAS ID only to a server that returns the session key, so that
Observer can directly locally decrypt all cyphertext sent by that UA Observer can directly locally decrypt all cyphertext sent by that UA
during that session (UAS operation). In either case, the server can during that session (UAS operation). In either case, the server can
be: a Public Safety USS; the Observer's own USS; or the UA's USS if be: a Public Safety USS, the Observer's own USS, or the UA's USS if
the latter can be determined (which under DRIP it can be, from the the latter can be determined (which under DRIP it can be, from the
UAS ID itself). PII can be protected unless the UAS is informed UAS ID itself). PII can be protected unless the UAS is informed
otherwise. This could come as part of UTM operation authorization. otherwise. This could come as part of UTM operation authorization.
It can be special instructions at the start or during an operation. It can be special instructions at the start or during an operation.
PII protection MUST not be used if the UAS loses connectivity to the PII protection MUST NOT be used if the UAS loses connectivity to the
USS. The UAS always has the option to abort the operation if PII USS. The UAS always has the option to abort the operation if PII
protection is disallowed. protection is disallowed.
11. References 12. References
11.1. Normative References 12.1. Normative References
[I-D.ietf-drip-reqs] [I-D.ietf-drip-reqs]
Card, S. W., Wiethuechter, A., Moskowitz, R., and A. Card, S. W., Wiethuechter, A., Moskowitz, R., and A.
Gurtov, "Drone Remote Identification Protocol (DRIP) Gurtov, "Drone Remote Identification Protocol (DRIP)
Requirements", Work in Progress, Internet-Draft, draft- Requirements", Work in Progress, Internet-Draft, draft-
ietf-drip-reqs-18, 8 September 2021, ietf-drip-reqs-18, 8 September 2021,
<https://www.ietf.org/archive/id/draft-ietf-drip-reqs- <https://www.ietf.org/archive/id/draft-ietf-drip-reqs-
18.txt>. 18.txt>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
11.2. Informative References 12.2. Informative References
[CTA2063A] ANSI, "Small Unmanned Aerial Systems Serial Numbers", [CTA2063A] ANSI, "Small Unmanned Aerial Systems Serial Numbers",
2019. 2019.
[Delegated] [Delegated]
European Union Aviation Safety Agency (EASA), "EU European Union Aviation Safety Agency (EASA), "EU
Commission Delegated Regulation 2019/945 of 12 March 2019 Commission Delegated Regulation 2019/945 of 12 March 2019
on unmanned aircraft systems and on third-country on unmanned aircraft systems and on third-country
operators of unmanned aircraft systems", 2019. operators of unmanned aircraft systems", 2019.
skipping to change at page 21, line 16 skipping to change at page 20, line 16
United States Federal Aviation Administration (FAA), United States Federal Aviation Administration (FAA),
"Unmanned Aircraft System (UAS) Traffic Management (UTM) "Unmanned Aircraft System (UAS) Traffic Management (UTM)
Concept of Operations (V2.0)", 2020, Concept of Operations (V2.0)", 2020,
<https://www.faa.gov/uas/research_development/ <https://www.faa.gov/uas/research_development/
traffic_management/media/UTM_ConOps_v2.pdf>. traffic_management/media/UTM_ConOps_v2.pdf>.
[FS_AEUA] "Study of Further Architecture Enhancement for UAV and [FS_AEUA] "Study of Further Architecture Enhancement for UAV and
UAM", 2021, <https://www.3gpp.org/ftp/tsg_sa/WG2_Arch/ UAM", 2021, <https://www.3gpp.org/ftp/tsg_sa/WG2_Arch/
TSGS2_147E_Electronic_2021-10/Docs/S2-2107092.zip>. TSGS2_147E_Electronic_2021-10/Docs/S2-2107092.zip>.
[I-D.ietf-drip-auth]
Wiethuechter, A., Card, S., and R. Moskowitz, "DRIP
Authentication Formats & Protocols for Broadcast Remote
ID", Work in Progress, Internet-Draft, draft-ietf-drip-
auth-04, 20 December 2021,
<https://www.ietf.org/archive/id/draft-ietf-drip-auth-
04.txt>.
[Implementing] [Implementing]
European Union Aviation Safety Agency (EASA), "EU European Union Aviation Safety Agency (EASA), "EU
Commission Implementing Regulation 2019/947 of 24 May 2019 Commission Implementing Regulation 2019/947 of 24 May 2019
on the rules and procedures for the operation of unmanned on the rules and procedures for the operation of unmanned
aircraft", 2019. aircraft", 2019.
[LAANC] United States Federal Aviation Administration (FAA), "Low [LAANC] United States Federal Aviation Administration (FAA), "Low
Altitude Authorization and Notification Capability", n.d., Altitude Authorization and Notification Capability", n.d.,
<https://www.faa.gov/uas/programs_partnerships/ <https://www.faa.gov/uas/programs_partnerships/
data_exchange/>. data_exchange/>.
skipping to change at page 22, line 19 skipping to change at page 21, line 27
[RFC7033] Jones, P., Salgueiro, G., Jones, M., and J. Smarr, [RFC7033] Jones, P., Salgueiro, G., Jones, M., and J. Smarr,
"WebFinger", RFC 7033, DOI 10.17487/RFC7033, September "WebFinger", RFC 7033, DOI 10.17487/RFC7033, September
2013, <https://www.rfc-editor.org/info/rfc7033>. 2013, <https://www.rfc-editor.org/info/rfc7033>.
[RFC7401] Moskowitz, R., Ed., Heer, T., Jokela, P., and T. [RFC7401] Moskowitz, R., Ed., Heer, T., Jokela, P., and T.
Henderson, "Host Identity Protocol Version 2 (HIPv2)", Henderson, "Host Identity Protocol Version 2 (HIPv2)",
RFC 7401, DOI 10.17487/RFC7401, April 2015, RFC 7401, DOI 10.17487/RFC7401, April 2015,
<https://www.rfc-editor.org/info/rfc7401>. <https://www.rfc-editor.org/info/rfc7401>.
[RFC7482] Newton, A. and S. Hollenbeck, "Registration Data Access
Protocol (RDAP) Query Format", RFC 7482,
DOI 10.17487/RFC7482, March 2015,
<https://www.rfc-editor.org/info/rfc7482>.
[RFC7483] Newton, A. and S. Hollenbeck, "JSON Responses for the
Registration Data Access Protocol (RDAP)", RFC 7483,
DOI 10.17487/RFC7483, March 2015,
<https://www.rfc-editor.org/info/rfc7483>.
[RFC7484] Blanchet, M., "Finding the Authoritative Registration Data [RFC7484] Blanchet, M., "Finding the Authoritative Registration Data
(RDAP) Service", RFC 7484, DOI 10.17487/RFC7484, March (RDAP) Service", RFC 7484, DOI 10.17487/RFC7484, March
2015, <https://www.rfc-editor.org/info/rfc7484>. 2015, <https://www.rfc-editor.org/info/rfc7484>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token [RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015, (JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>. <https://www.rfc-editor.org/info/rfc7519>.
[RFC8004] Laganier, J. and L. Eggert, "Host Identity Protocol (HIP) [RFC8004] Laganier, J. and L. Eggert, "Host Identity Protocol (HIP)
Rendezvous Extension", RFC 8004, DOI 10.17487/RFC8004, Rendezvous Extension", RFC 8004, DOI 10.17487/RFC8004,
October 2016, <https://www.rfc-editor.org/info/rfc8004>. October 2016, <https://www.rfc-editor.org/info/rfc8004>.
[RFC8005] Laganier, J., "Host Identity Protocol (HIP) Domain Name [RFC8005] Laganier, J., "Host Identity Protocol (HIP) Domain Name
System (DNS) Extension", RFC 8005, DOI 10.17487/RFC8005, System (DNS) Extension", RFC 8005, DOI 10.17487/RFC8005,
October 2016, <https://www.rfc-editor.org/info/rfc8005>. October 2016, <https://www.rfc-editor.org/info/rfc8005>.
[RFC8032] Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital
Signature Algorithm (EdDSA)", RFC 8032,
DOI 10.17487/RFC8032, January 2017,
<https://www.rfc-editor.org/info/rfc8032>.
[RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig, [RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
"CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392, "CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392,
May 2018, <https://www.rfc-editor.org/info/rfc8392>. May 2018, <https://www.rfc-editor.org/info/rfc8392>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object [RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949, Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020, DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>. <https://www.rfc-editor.org/info/rfc8949>.
[RFC9082] Hollenbeck, S. and A. Newton, "Registration Data Access
Protocol (RDAP) Query Format", STD 95, RFC 9082,
DOI 10.17487/RFC9082, June 2021,
<https://www.rfc-editor.org/info/rfc9082>.
[RFC9083] Hollenbeck, S. and A. Newton, "JSON Responses for the
Registration Data Access Protocol (RDAP)", STD 95,
RFC 9083, DOI 10.17487/RFC9083, June 2021,
<https://www.rfc-editor.org/info/rfc9083>.
[TS-22.825] [TS-22.825]
3GPP, "Study on Remote Identification of Unmanned Aerial 3GPP, "Study on Remote Identification of Unmanned Aerial
Systems (UAS)", n.d., Systems (UAS)", n.d.,
<https://portal.3gpp.org/desktopmodules/Specifications/ <https://portal.3gpp.org/desktopmodules/Specifications/
SpecificationDetails.aspx?specificationId=3527>. SpecificationDetails.aspx?specificationId=3527>.
[U-Space] European Organization for the Safety of Air Navigation [U-Space] European Organization for the Safety of Air Navigation
(EUROCONTROL), "U-space Concept of Operations", 2019, (EUROCONTROL), "U-space Concept of Operations", 2019,
<https://www.sesarju.eu/sites/default/files/documents/u- <https://www.sesarju.eu/sites/default/files/documents/u-
space/CORUS%20ConOps%20vol2.pdf>. space/CORUS%20ConOps%20vol2.pdf>.
 End of changes. 77 change blocks. 
240 lines changed or deleted 252 lines changed or added

This html diff was produced by rfcdiff 1.48. The latest version is available from http://tools.ietf.org/tools/rfcdiff/