draft-ietf-lisp-gpe-05.txt   draft-ietf-lisp-gpe-06.txt 
Internet Engineering Task Force F. Maino, Ed. Internet Engineering Task Force F. Maino, Ed.
Internet-Draft Cisco Internet-Draft Cisco
Intended status: Standards Track J. Lemon Intended status: Standards Track J. Lemon
Expires: February 16, 2019 Broadcom Expires: March 24, 2019 Broadcom
P. Agarwal P. Agarwal
Innovium Innovium
D. Lewis D. Lewis
M. Smith M. Smith
Cisco Cisco
August 15, 2018 September 20, 2018
LISP Generic Protocol Extension LISP Generic Protocol Extension
draft-ietf-lisp-gpe-05 draft-ietf-lisp-gpe-06
Abstract Abstract
This document describes extentions to the Locator/ID Separation This document describes extentions to the Locator/ID Separation
Protocol (LISP) Data-Plane, via changes to the LISP header, to Protocol (LISP) Data-Plane, via changes to the LISP header, to
support multi-protocol encapsulation. support multi-protocol encapsulation.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
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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 http://datatracker.ietf.org/drafts/current/. Drafts is at http://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 February 16, 2019. This Internet-Draft will expire on March 24, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2018 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 Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
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include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Conventions . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Definition of Terms . . . . . . . . . . . . . . . . . . . 3 1.2. Definition of Terms . . . . . . . . . . . . . . . . . . . 3
2. LISP Header Without Protocol Extensions . . . . . . . . . . . 3 2. LISP Header Without Protocol Extensions . . . . . . . . . . . 3
3. Generic Protocol Extension for LISP (LISP-GPE) . . . . . . . 3 3. Generic Protocol Extension for LISP (LISP-GPE) . . . . . . . 4
4. Backward Compatibility . . . . . . . . . . . . . . . . . . . 5 3.1. Payload Specific Transport Interactions . . . . . . . . . 6
3.1.1. Payload Specific Transport Interactions for Ethernet
Encapsulated Payloads . . . . . . . . . . . . . . . . 6
3.1.2. Payload Specific Transport Interactions for NSH
Encapsulated Payloads . . . . . . . . . . . . . . . . 7
4. Backward Compatibility . . . . . . . . . . . . . . . . . . . 7
4.1. Use of "Multiple Data-Planes" LCAF to Determine ETR 4.1. Use of "Multiple Data-Planes" LCAF to Determine ETR
Capabilities . . . . . . . . . . . . . . . . . . . . . . 6 Capabilities . . . . . . . . . . . . . . . . . . . . . . 7
4.2. Type of Service . . . . . . . . . . . . . . . . . . . . . 6 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
4.3. VLAN Identifier (VID) . . . . . . . . . . . . . . . . . . 6 5.1. LISP-GPE Next Protocol Registry . . . . . . . . . . . . . 8
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 5.2. Multiple Data-Planes Encapsulation Bitmap Registry . . . 8
5.1. LISP-GPE Next Protocol Registry . . . . . . . . . . . . . 6 6. Security Considerations . . . . . . . . . . . . . . . . . . . 9
5.2. Multiple Data-Planes Encapsulation Bitmap Registry . . . 7 7. Acknowledgements and Contributors . . . . . . . . . . . . . . 10
6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
7. Acknowledgements and Contributors . . . . . . . . . . . . . . 8 8.1. Normative References . . . . . . . . . . . . . . . . . . 10
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 8.2. Informative References . . . . . . . . . . . . . . . . . 11
8.1. Normative References . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12
8.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
The LISP Data-Plane is defined in [I-D.ietf-lisp-rfc6830bis]. It The LISP Data-Plane is defined in [I-D.ietf-lisp-rfc6830bis]. It
specifies an encapsulation format that carries IPv4 or IPv6 packets specifies an encapsulation format that carries IPv4 or IPv6 packets
(henceforth jointly referred to as IP) in a LISP header and outer (henceforth jointly referred to as IP) in a LISP header and outer
UDP/IP transport. UDP/IP transport.
The LISP Data-Plane header does not specify the protocol being The LISP Data-Plane header does not specify the protocol being
encapsulated and therefore is currently limited to encapsulating only encapsulated and therefore is currently limited to encapsulating only
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[I-D.ietf-lisp-rfc6830bis], to indicate the inner protocol, enabling [I-D.ietf-lisp-rfc6830bis], to indicate the inner protocol, enabling
the encapsulation of Ethernet, IP or any other desired protocol all the encapsulation of Ethernet, IP or any other desired protocol all
the while ensuring compatibility with existing LISP deployments. the while ensuring compatibility with existing LISP deployments.
A flag in the LISP header, called the P-bit, is used to signal the A flag in the LISP header, called the P-bit, is used to signal the
presence of the 8-bit Next Protocol field. The Next Protocol field, presence of the 8-bit Next Protocol field. The Next Protocol field,
when present, uses 8 bits of the field allocated to the echo-noncing when present, uses 8 bits of the field allocated to the echo-noncing
and map-versioning features. The two features are still available, and map-versioning features. The two features are still available,
albeit with a reduced length of Nonce and Map-Version. albeit with a reduced length of Nonce and Map-Version.
LISP-GPE MAY also be used to extend the LISP Data-Plane header, that
has allocated all by defining a Next Protocol "shim" header that
implements new data plane functions not supported in the LISP header.
As an example, the use of the Network Service Header (NSH) with LISP-
GPE, can be considered an extension to add support in the Data-Plane
for Network Service Chaining functionalities.
1.1. Conventions 1.1. 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 here. capitals, as shown here.
1.2. Definition of Terms 1.2. Definition of Terms
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0x2 : IPv6 0x2 : IPv6
0x3 : Ethernet 0x3 : Ethernet
0x4 : Network Service Header (NSH) [RFC8300] 0x4 : Network Service Header (NSH) [RFC8300]
The values are tracked in an IANA registry as described in The values are tracked in an IANA registry as described in
Section 5.1. Section 5.1.
3.1. Payload Specific Transport Interactions
To ensure that protocols that are encapsulated in LISP-GPE will work
well from a transport interaction perspective, the specification of a
new encapsulated payload MUST contain an analysis of how LISP-GPE
SHOULD deal with outer UDP Checksum, DSCP mapping, and Explicit
Congestion Notification (ECN) bits whenever they apply to the new
encapsulated payload.
For IP payloads, section 5.3 of [I-D.ietf-lisp-rfc6830bis] specifies
how to handle UDP Checksums encouraging implementors to consider UDP
checksum usage guidelines in section 3.4 of [RFC8085] when it is
desirable to protect UDP and LISP headers against corruption. Each
new encapsulated payloads, when registered with LISP-GPE, MUST be
accompanied by a similar analysis.
Encapsulated payloads may have a priority field that may or may not
be mapped to the DSCP field of the outer IP header (part of Type of
Service in IPv4 or Traffic Class in IPv6). Such new encapsulated
payloads, when registered with LISP-GPE, MUST be accompanied by an
analysis similar to the one performed in Section 3.1.1 of this
document for Ethernet payloads.
Encapsulated payloads may have Explicit Congestion Notification
mechanisms that may or may not be mapped to the outer IP header ECN
field. Such new encapsulated payolads, when registered with LISP-
GPE, MUST be accompanied by a set of guidelines derived from
[RFC6040].
The rest of this section specifies payload specific transport
interactions considerations for the two new LISP-GPE encapsulated
payloads specified in this document: Ethernet and NSH.
3.1.1. Payload Specific Transport Interactions for Ethernet
Encapsulated Payloads
The UDP Checksum considerations specified in section 5.3 of
[I-D.ietf-lisp-rfc6830bis] apply to Ethernet Encapsulated Payloads.
Implementors are encouraged to consider the UDP checksum usage
guidelines in section 3.4 of [RFC8085] when it is desirable to
protect UDP, LISP and Ethernet headers against corruption.
When a LISP-GPE router performs Ethernet encapsulation, the inner
802.1Q [IEEE.802.1Q_2014] priority code point (PCP) field MAY be
mapped from the encapsulated frame to the Type of Service field in
the outer IPv4 header, or in the case of IPv6 the 'Traffic Class'
field.
When a LISP-GPE router performs Ethernet encapsulation, the inner
header 802.1Q [IEEE.802.1Q_2014] VLAN Identifier (VID) MAY be mapped
to, or used to determine the LISP Instance IDentifier (IID) field.
3.1.2. Payload Specific Transport Interactions for NSH Encapsulated
Payloads
The UDP Checksum considerations specified in section 5.3 of
[I-D.ietf-lisp-rfc6830bis] apply to NSH Encapsulated Payloads.
Implementors are encouraged to consider the UDP checksum usage
guidelines in section 3.4 of [RFC8085] when it is desirable to
protect UDP, LISP, and NSH headers against corruption.
When a LISP-GPE router performs an NSH encapsulation, DSCP and ECN
values MAY be mapped as specified for the Next Protocol encapsulated
by NSH (namely IPv4, IPv6 and Ethernet).
4. Backward Compatibility 4. Backward Compatibility
LISP-GPE uses the same UDP destination port (4341) allocated to LISP. LISP-GPE uses the same UDP destination port (4341) allocated to LISP.
The next Section describes a method to determine the Data-Plane The next Section describes a method to determine the Data-Plane
capabilities of a LISP ETR, based on the use of the "Multiple Data- capabilities of a LISP ETR, based on the use of the "Multiple Data-
Planes" LISP Canonical Address Format (LCAF) type defined in Planes" LISP Canonical Address Format (LCAF) type defined in
[RFC8060]. Other mechanisms can be used, including static ETR/ITR [RFC8060]. Other mechanisms can be used, including static ETR/ITR
(xTR) configuration, but are out of the scope of this document. (xTR) configuration, but are out of the scope of this document.
When encapsulating IP packets to a non LISP-GPE capable router the When encapsulating IP packets to a non LISP-GPE capable router the
P-bit MUST be set to 0. That is, the encapsulation format defined in P-bit MUST be set to 0. That is, the encapsulation format defined in
this document MUST NOT be sent to a router that has not indicated this document MUST NOT be sent to a router that has not indicated
that it supports this specification because such a router would that it supports this specification because such a router would
ignore the P-bit (as described in [I-D.ietf-lisp-rfc6830bis]) and so ignore the P-bit (as described in [I-D.ietf-lisp-rfc6830bis]) and so
would misinterpret the other LISP header fields possibly causing would misinterpret the other LISP header fields possibly causing
significant errors. significant errors.
A LISP-GPE router MUST NOT encapsulate non-IP packets to a non LISP- A LISP-GPE router MUST NOT encapsulate non-IP packets (that have the
GPE capable router. P-bit set to 1) to a non-LISP-GPE capable router.
4.1. Use of "Multiple Data-Planes" LCAF to Determine ETR Capabilities 4.1. Use of "Multiple Data-Planes" LCAF to Determine ETR Capabilities
LISP Canonical Address Format (LCAF) [RFC8060] defines the "Multiple LISP Canonical Address Format (LCAF) [RFC8060] defines the "Multiple
Data-Planes" LCAF type, that can be included by an ETR in a Map-Reply Data-Planes" LCAF type, that can be included by an ETR in a Map-Reply
to encode the encapsulation formats supported by a given RLOC. In to encode the encapsulation formats supported by a given RLOC. In
this way an ITR can be made aware of the capability to support LISP- this way an ITR can be made aware of the capability to support LISP-
GPE, as well as other encapsulations, on a given RLOC of that ETR. GPE, as well as other encapsulations, on a given RLOC of that ETR.
The 3rd 32-bit word of the "Multiple Data-Planes" LCAF type, as The 3rd 32-bit word of the "Multiple Data-Planes" LCAF type, as
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tracked in an IANA registry as described in Section 5.2. tracked in an IANA registry as described in Section 5.2.
This document defines bit 24 in the third 32-bit word of the This document defines bit 24 in the third 32-bit word of the
"Multiple Data-Planes" LCAF as: "Multiple Data-Planes" LCAF as:
g-Bit: The RLOCs listed in the Address Family Identifier (AFI) g-Bit: The RLOCs listed in the Address Family Identifier (AFI)
encoded addresses in the next longword can accept LISP-GPE encoded addresses in the next longword can accept LISP-GPE
(Generic Protocol Extension) encapsulation using destination UDP (Generic Protocol Extension) encapsulation using destination UDP
port 4341 port 4341
4.2. Type of Service
When a LISP-GPE router performs Ethernet encapsulation, the inner
802.1Q [IEEE.802.1Q_2014] priority code point (PCP) field MAY be
mapped from the encapsulated frame to the Type of Service field in
the outer IPv4 header, or in the case of IPv6 the 'Traffic Class'
field
4.3. VLAN Identifier (VID)
When a LISP-GPE router performs Ethernet encapsulation, the inner
header 802.1Q [IEEE.802.1Q_2014] VLAN Identifier (VID) MAY be mapped
to, or used to determine the LISP Instance IDentifier (IID) field.
5. IANA Considerations 5. IANA Considerations
5.1. LISP-GPE Next Protocol Registry 5.1. LISP-GPE Next Protocol Registry
IANA is requested to set up a registry of LISP-GPE "Next Protocol". IANA is requested to set up a registry of LISP-GPE "Next Protocol".
These are 8-bit values. Next Protocol values in the table below are These are 8-bit values. Next Protocol values in the table below are
defined in this document. New values are assigned via Standards defined in this document. New values are assigned via Standards
Action [RFC8126]. The protocols that are being assigned values do Action [RFC8126]. The protocols that are being assigned values do
not themselves need to be IETF standards track protocols. not themselves need to be IETF standards track protocols.
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| 30 | l | Layer 2 LISP (LISP-L2) | [RFC8060] | | 30 | l | Layer 2 LISP (LISP-L2) | [RFC8060] |
| 31 | L | Locator/ID Separation Protocol | [RFC8060] | | 31 | L | Locator/ID Separation Protocol | [RFC8060] |
| | | (LISP) | | | | | (LISP) | |
+----------+-------+------------------------------------+-----------+ +----------+-------+------------------------------------+-----------+
6. Security Considerations 6. Security Considerations
LISP-GPE security considerations are similar to the LISP security LISP-GPE security considerations are similar to the LISP security
considerations and mitigation techniques documented in [RFC7835]. considerations and mitigation techniques documented in [RFC7835].
The Echo Nonce Algorithm described in [I-D.ietf-lisp-rfc6830bis]
relies on the nonce to detect reachability from ITR to ETR. In LISP-
GPE the use of a 16-bit nonce, compared with the 24-bit nonce used in
LISP, increases the probability of an off-path attacker to correctly
guess the nonce and force the ITR to believe that a non-reachable
RLOC is reachable. However, the use of common anti-spoofing
mechanisms such as uRPF prevents this form of attack.
LISP-GPE, as many encapsulations that use optional extensions, is
subject to on-path adversaries that by manipulating the g-Bit and the
packet itself can remove part of the payload. Typical integrity
protection mechanisms (such as IPsec) SHOULD be used in combination
with LISP-GPE by those protocol extensions that want to protect from
on-path attackers.
With LISP-GPE, issues such as data-plane spoofing, flooding, and With LISP-GPE, issues such as data-plane spoofing, flooding, and
traffic redirection may depend on the particular protocol payload traffic redirection may depend on the particular protocol payload
encapsulated. encapsulated.
7. Acknowledgements and Contributors 7. Acknowledgements and Contributors
A special thank you goes to Dino Farinacci for his guidance and A special thank you goes to Dino Farinacci for his guidance and
detailed review. detailed review.
This Workking Group (WG) document originated as draft-lewis-lisp-gpe; This Workking Group (WG) document originated as draft-lewis-lisp-gpe;
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o Puneet Agarwal, Innovium o Puneet Agarwal, Innovium
8. References 8. References
8.1. Normative References 8.1. Normative References
[I-D.ietf-lisp-6834bis] [I-D.ietf-lisp-6834bis]
Iannone, L., Saucez, D., and O. Bonaventure, "Locator/ID Iannone, L., Saucez, D., and O. Bonaventure, "Locator/ID
Separation Protocol (LISP) Map-Versioning", draft-ietf- Separation Protocol (LISP) Map-Versioning", draft-ietf-
lisp-6834bis-00 (work in progress), July 2018. lisp-6834bis-02 (work in progress), September 2018.
[I-D.ietf-lisp-rfc6830bis] [I-D.ietf-lisp-rfc6830bis]
Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A.
Cabellos-Aparicio, "The Locator/ID Separation Protocol Cabellos-Aparicio, "The Locator/ID Separation Protocol
(LISP)", draft-ietf-lisp-rfc6830bis-14 (work in progress), (LISP)", draft-ietf-lisp-rfc6830bis-18 (work in progress),
July 2018. September 2018.
[IEEE.802.1Q_2014] [IEEE.802.1Q_2014]
IEEE, "IEEE Standard for Local and metropolitan area IEEE, "IEEE Standard for Local and metropolitan area
networks--Bridges and Bridged Networks", IEEE 802.1Q-2014, networks--Bridges and Bridged Networks", IEEE 802.1Q-2014,
DOI 10.1109/ieeestd.2014.6991462, December 2014, DOI 10.1109/ieeestd.2014.6991462, December 2014,
<http://ieeexplore.ieee.org/servlet/ <http://ieeexplore.ieee.org/servlet/
opac?punumber=6991460>. opac?punumber=6991460>.
[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, <https://www.rfc- DOI 10.17487/RFC2119, March 1997, <https://www.rfc-
editor.org/info/rfc2119>. editor.org/info/rfc2119>.
8.2. Informative References 8.2. Informative References
[RFC6040] Briscoe, B., "Tunnelling of Explicit Congestion
Notification", RFC 6040, DOI 10.17487/RFC6040, November
2010, <https://www.rfc-editor.org/info/rfc6040>.
[RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger,
L., Sridhar, T., Bursell, M., and C. Wright, "Virtual L., Sridhar, T., Bursell, M., and C. Wright, "Virtual
eXtensible Local Area Network (VXLAN): A Framework for eXtensible Local Area Network (VXLAN): A Framework for
Overlaying Virtualized Layer 2 Networks over Layer 3 Overlaying Virtualized Layer 2 Networks over Layer 3
Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014,
<https://www.rfc-editor.org/info/rfc7348>. <https://www.rfc-editor.org/info/rfc7348>.
[RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID [RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID
Separation Protocol (LISP) Threat Analysis", RFC 7835, Separation Protocol (LISP) Threat Analysis", RFC 7835,
DOI 10.17487/RFC7835, April 2016, <https://www.rfc- DOI 10.17487/RFC7835, April 2016, <https://www.rfc-
editor.org/info/rfc7835>. editor.org/info/rfc7835>.
[RFC8060] Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical [RFC8060] Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical
Address Format (LCAF)", RFC 8060, DOI 10.17487/RFC8060, Address Format (LCAF)", RFC 8060, DOI 10.17487/RFC8060,
February 2017, <https://www.rfc-editor.org/info/rfc8060>. February 2017, <https://www.rfc-editor.org/info/rfc8060>.
[RFC8085] Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage
Guidelines", BCP 145, RFC 8085, DOI 10.17487/RFC8085,
March 2017, <https://www.rfc-editor.org/info/rfc8085>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26, Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017, RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>. <https://www.rfc-editor.org/info/rfc8126>.
[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>.
[RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed.,
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