rfc9423.original.xml   rfc9423.xml 
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<rfc xmlns:xi="http://www.w3.org/2001/XInclude" ipr="trust200902" docName="draft -ietf-core-target-attr-06" number="9423" submissionType="IETF" category="info" c
-ietf-core-target-attr-06" category="info" submissionType="IETF" tocInclude="tru onsensus="true" tocInclude="true" sortRefs="true" symRefs="true" updates="" obso
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<front> <front>
<title abbrev="CoRE Target Attributes Registry">CoRE Target Attributes Regis <title abbrev="CoRE Target Attributes Registry">Constrained RESTful Environm
try</title> ents (CoRE) Target Attributes Registry</title>
<seriesInfo name="Internet-Draft" value="draft-ietf-core-target-attr-06"/>
<seriesInfo name="RFC" value="9423"/>
<author initials="C." surname="Bormann" fullname="Carsten Bormann"> <author initials="C." surname="Bormann" fullname="Carsten Bormann">
<organization>Universität Bremen TZI</organization> <organization>Universität Bremen TZI</organization>
<address> <address>
<postal> <postal>
<street>Postfach 330440</street> <street>Postfach 330440</street>
<city>Bremen</city> <city>Bremen</city>
<code>D-28359</code> <code>D-28359</code>
<country>Germany</country> <country>Germany</country>
</postal> </postal>
<phone>+49-421-218-63921</phone> <phone>+49-421-218-63921</phone>
<email>cabo@tzi.org</email> <email>cabo@tzi.org</email>
</address> </address>
</author> </author>
<date year="2023" month="October" day="11"/> <date year="2024" month="March"/>
<workgroup>CoRE Working group</workgroup> <area>art</area>
<keyword>Internet-Draft</keyword> <workgroup>core</workgroup>
<abstract>
<?line 57?>
<t>The Constrained RESTful Environments (CoRE) specifications apply Web <keyword>CoAP</keyword>
<keyword>Web Linking</keyword>
<keyword>Resource Discovery</keyword>
<abstract>
<t>The Constrained RESTful Environments (CoRE) specifications apply web
technologies to constrained environments. technologies to constrained environments.
One important such technology is Web Linking (RFC 8288), which CoRE One such important technology is Web Linking (RFC 8288), which CoRE
specifications use as the basis for a number of discovery protocols, such as the specifications use as the basis for a number of discovery protocols, such as the
Link Format (RFC 6690) in CoAP's Resource Discovery Protocol (Section 7.2 Link Format (RFC 6690) in the Constrained Application Protocol's (CoAP's) resour
of RFC7252) and the Resource Directory (RD, RFC 9176).</t> ce discovery process (Section 7.2
of RFC 7252) and the Resource Directory (RD) (RFC 9176).
</t>
<t>Web Links can have target attributes, the names of which are not <t>Web Links can have target attributes, the names of which are not
generally coordinated by the Web Linking specification (Section 2.2 of generally coordinated by the Web Linking specification (Section 2.2 of
RFC 8288). RFC 8288).
This document introduces an IANA registry for coordinating names of target This document introduces an IANA registry for coordinating names of target
attributes when used in CoRE. attributes when used in CoRE.
It updates the RD Parameters IANA Registry created by RFC 9176 to coordinate wit h It updates the "RD Parameters" IANA registry created by RFC 9176 to coordinate w ith
this registry.</t> this registry.</t>
</abstract> </abstract>
<note removeInRFC="true">
<name>About This Document</name>
<t>
Status information for this document may be found at <eref target="https
://datatracker.ietf.org/doc/draft-ietf-core-target-attr/"/>.
</t>
<t>
Discussion of this document takes place on the
core Working Group mailing list (<eref target="mailto:core@ietf.org"/>),
which is archived at <eref target="https://mailarchive.ietf.org/arch/bro
wse/core/"/>.
Subscribe at <eref target="https://www.ietf.org/mailman/listinfo/core/"/
>.
</t>
<t>Source for this draft and an issue tracker can be found at
<eref target="https://github.com/core-wg/core-target-attr"/>.</t>
</note>
</front> </front>
<middle> <middle>
<?line 74?>
<section anchor="intro"> <section anchor="intro">
<name>Introduction</name> <name>Introduction</name>
<t>The Constrained RESTful Environments (CoRE) specifications apply Web <t>The Constrained RESTful Environments (CoRE) specifications apply web
technologies to constrained environments. technologies to constrained environments.
One important such technology is Web Linking <xref target="RFC8288"/>, which CoR E One such important technology is Web Linking <xref target="RFC8288"/>, which CoR E
specifications use as the basis for a number of discovery protocols, such as the specifications use as the basis for a number of discovery protocols, such as the
Link Format <xref target="RFC6690"/> in CoAP's Resource Discovery Protocol (<xre Link Format <xref target="RFC6690"/> in the Constrained Application Protocol's (
f section="7.2" sectionFormat="of" target="RFC7252"/>) and the Resource Director CoAP's) resource discovery process (<xref section="7.2" sectionFormat="of" targe
y <xref target="RFC9176"/>.</t> t="RFC7252"/>) and the Resource Directory (RD)
<xref target="RFC9176"/>.</t>
<t>Web Links can have target attributes. <t>Web Links can have target attributes.
The original Web Linking specification (<xref section="3" sectionFormat="of" tar get="RFC5988"/>) did not attempt The original Web Linking specification (<xref section="3" sectionFormat="of" tar get="RFC5988"/>) did not attempt
to coordinate names of target attributes except for providing common to coordinate names of target attributes except for providing common
target attributes for use in the Link HTTP header. target attributes for use in the Link HTTP header.
The current revision of that specification clarifies (<xref section="2.2" sectio The current revision of that specification (<xref section="2.2" sectionFormat="o
nFormat="of" target="RFC8288"/>):</t> f" target="RFC8288"/>) clarifies as follows:</t>
<!-- DNE; verified -->
<blockquote> <blockquote>
<t>This specification does not attempt to coordinate the name of target <t>This specification does not attempt to coordinate the name of target
attributes, their cardinality, or use. Those creating and attributes, their cardinality, or use. Those creating and
maintaining serialisations <bcp14>SHOULD</bcp14> coordinate their target attr ibutes maintaining serialisations <bcp14>SHOULD</bcp14> coordinate their target attr ibutes
to avoid conflicts in semantics or syntax and <bcp14>MAY</bcp14> define their own to avoid conflicts in semantics or syntax and <bcp14>MAY</bcp14> define their own
registries of target attributes.</t> registries of target attributes.</t>
</blockquote> </blockquote>
<t>This document introduces an IANA registry for coordinating names of tar get <t>This document introduces an IANA registry for coordinating names of tar get
attributes when used in CoRE, with attributes when used in CoRE, with
specific instructions for the Designated Expert for this registry (<xref target= specific instructions for the designated expert for this registry (<xref target=
"de-instructions"/>). "de-instructions"/>).
It updates the RD Parameters IANA Registry created by <xref target="RFC9176"/> t It updates the "RD Parameters" IANA registry created by <xref target="RFC9176"/>
o coordinate with to coordinate with
this registry.</t> this registry.</t>
<t>With a registry now available, registration of target attributes is str ongly encouraged. <t>With this registry now available, registration of target attributes is strongly encouraged.
The incentive is that an unregistered attribute name might be registered with a different meaning at any time.</t> The incentive is that an unregistered attribute name might be registered with a different meaning at any time.</t>
<section anchor="terminology"> <section anchor="terminology">
<name>Terminology</name> <name>Terminology</name>
<t>The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp <t>The key words "<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>",
14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>",
NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECO "<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>",
MMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>SHOULD NOT</bcp14>",
"<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document are to be i "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>",
nterpreted as "<bcp14>MAY</bcp14>", and "<bcp14>OPTIONAL</bcp14>" in this document
described in BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and are to be interpreted as described in BCP&nbsp;14
only when, they <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only
appear in all capitals, as shown here.</t> when, they appear in all capitals, as shown here.</t>
<?line -18?>
</section> </section>
</section> </section>
<section anchor="iana-considerations"> <section anchor="iana-considerations">
<name>IANA Considerations</name> <name>IANA Considerations</name>
<t>This specification creates a new Target Attributes registry in <t>Per this specification, IANA has created a new "Target Attributes" regi stry in
the "Constrained RESTful Environments (CoRE) Parameters" registry group <xref ta rget="IANA.core-parameters"/>, with the policy the "Constrained RESTful Environments (CoRE) Parameters" registry group <xref ta rget="IANA.core-parameters"/>, with the policy
"Expert Review" (<xref section="4.5" sectionFormat="of" target="BCP26"/>).</t> "Expert Review" (Section <xref section="4.5" sectionFormat="bare" target="RFC812 6"/> of RFC 8126 <xref target="BCP26"/>).</t>
<section anchor="de-instructions"> <section anchor="de-instructions">
<name>Instructions for the Designated Expert</name> <name>Instructions for the Designated Expert</name>
<t>The expert is requested to guide the registrant towards reasonably <t>The expert is requested to guide the registrant towards reasonably
short target attribute names where the shortness will help conserve short target attribute names where the shortness will help conserve
resources in constrained systems, but also to be frugal in the resources in constrained systems, but to also be frugal in the
allocation of very short names, keeping them in reserve for allocation of very short names, keeping them in reserve for
applications that are likely to enjoy wide use and can make good use applications that are likely to enjoy wide use and can make good use
of their shortness.</t> of their shortness.</t>
<t>The expert is also instructed to direct the registrant to provide a <t>The expert is also instructed to direct the registrant to provide a
specification (<xref section="4.6" sectionFormat="of" target="BCP26"/>), but can specification (Section <xref section="4.6" sectionFormat="bare" target="RFC8126"
make exceptions, /> of RFC 8126 <xref target="BCP26"/>) but can make exceptions --
for instance when a specification is not available at the time of for instance, when a specification is not available at the time of
registration but is likely forthcoming.</t> registration but is likely forthcoming.</t>
<t>Any questions or issues that might interest a wider audience might be <t>Any questions or issues that might interest a wider audience might be
raised by the expert on the core-parameters@ietf.org mailing list for raised by the expert on the core-parameters@ietf.org mailing list for
a time-limited discussion. a time-limited discussion.
This might include security considerations, or opportunities for This might include security considerations, or opportunities for
orchestration, e.g., when different names with similar intent are orchestration, e.g., when different names with similar intent are
being or could be registered.</t> being or could be registered.</t>
<t>If the expert becomes aware of target attributes that are deployed an d <t>If the expert becomes aware of target attributes that are deployed an d
in use, they may also initiate a registration on their own if in use, they may also initiate a registration on their own if
they deem such a registration can avert potential future collisions.</t> they deem that such a registration can avert potential future collisions.</t>
</section> </section>
<section anchor="structure-of-entries"> <section anchor="structure-of-entries">
<name>Structure of Entries</name> <name>Structure of Entries</name>
<t>Each entry in the registry must include:</t> <t>Each entry in the registry must include the following:</t>
<dl newline="true"> <dl newline="true">
<dt>Attribute Name:</dt> <dt>Attribute Name:</dt>
<dd> <dd>
<t>a lower case ASCII <xref target="STD80"/> string that starts with a letter and can <t>A lowercase ASCII string <xref target="STD80"/> that starts with a letter and can
contain digits and hyphen-minus characters afterward contain digits and hyphen-minus characters afterward
(<tt>[a-z][-a-z0-9]*</tt>). (<tt>[a-z][-a-z0-9]*</tt>).
(Note that <xref target="RFC8288"/> requires target attribute names to be (Note that <xref target="RFC8288"/> requires target attribute names to be
interpreted in a case-insensitive way; the restriction to lower case interpreted in a case-insensitive way; the restriction to lowercase
here ensures that they are registered in a predictable form).</t> here ensures that they are registered in a predictable form.)</t>
</dd> </dd>
<dt>Brief description:</dt> <dt>Brief Description:</dt>
<dd> <dd>
<t>a brief description</t> <t>A brief description.</t>
</dd> </dd>
<dt>Change Controller:</dt> <dt>Change Controller:</dt>
<dd> <dd>
<t>see <xref section="2.3" sectionFormat="of" target="BCP26"/></t> <t>See Section <xref section="2.3" sectionFormat="bare" target="RFC8 126"/> of RFC 8126 <xref target="BCP26"/>.</t>
</dd> </dd>
<dt>Reference:</dt> <dt>Reference:</dt>
<dd> <dd>
<t>a reference document that provides a description of the target <t>A reference document that provides a description of the target
attribute, including the semantics for when the target attribute attribute, including the semantics for when the target attribute
appears more than once in a link.</t> appears more than once in a link.</t>
</dd> </dd>
</dl> </dl>
</section> </section>
<section anchor="initial-entries"> <section anchor="initial-entries">
<name>Initial Entries</name> <name>Initial Entries</name>
<t>Initial entries in this registry are listed in <xref target="pre-reg" />.</t> <t>Initial entries in this registry are listed in <xref target="pre-reg" />.</t>
<table anchor="pre-reg"> <table anchor="pre-reg">
<name>Initial Entries in the Target Attributes Registry</name> <name>Initial Entries in the Target Attributes Registry</name>
<thead> <thead>
<tr> <tr>
<th align="left">Attribute Name</th> <th align="left">Attribute Name</th>
<th align="left">Brief description</th> <th align="left">Brief Description</th>
<th align="left">Change Controller</th> <th align="left">Change Controller</th>
<th align="left">Reference</th> <th align="left">Reference</th>
</tr> </tr>
</thead> </thead>
<tbody> <tbody>
<tr> <tr>
<td align="left">href</td> <td align="left">href</td>
<td align="left">reserved (not useful as target attribute name)</t d> <td align="left">reserved (not useful as target attribute name)</t d>
<td align="left">IETF</td> <td align="left">IETF</td>
<td align="left"> <td align="left">
skipping to change at line 310 skipping to change at line 308
</tr> </tr>
<tr> <tr>
<td align="left">et</td> <td align="left">et</td>
<td align="left">Endpoint Type (with rt="core.rd-ep")</td> <td align="left">Endpoint Type (with rt="core.rd-ep")</td>
<td align="left">IETF</td> <td align="left">IETF</td>
<td align="left"> <td align="left">
<xref section="9.3" sectionFormat="of" target="RFC9176"/></td> <xref section="9.3" sectionFormat="of" target="RFC9176"/></td>
</tr> </tr>
</tbody> </tbody>
</table> </table>
<t>A number of names are reserved as they are used for parameters in <t>A number of names are reserved, as they are used for parameters in
links other than target attributes. links other than target attributes.
A further set of target attributes is predefined in <xref target="RFC8288"/> and is A further set of target attributes is predefined in <xref target="RFC8288"/> and is
imported into this registry.</t> imported into this registry.</t>
<t><xref section="9.3" sectionFormat="of" target="RFC9176"/> created the "RD Parameters" IANA registry. <t><xref section="9.3" sectionFormat="of" target="RFC9176"/> created the "RD Parameters" IANA registry.
This document requests IANA to add the following note to that registry:</t> Per this document, IANA has added the following note to that registry:</t>
<ul empty="true"> <blockquote>Note: In accordance with RFC 9423, all entries with the
<li> "A" flag set, including new ones, <bcp14>MUST</bcp14> also be registered in the
<t>Note: In accordance with [this document], all entries with the "A "Target Attributes" registry <xref target="IANA.core-parameters"/>.</blockquote>
" flag set, including new ones, <bcp14>MUST</bcp14> also be registered in the "T
arget Attributes" registry <xref target="IANA.core-parameters"/>.</t>
</li>
</ul>
</section> </section>
</section> </section>
<section anchor="security-considerations"> <section anchor="security-considerations">
<name>Security considerations</name> <name>Security Considerations</name>
<t>The security considerations of <xref target="RFC8288"/> apply, as do th ose of the <t>The security considerations of <xref target="RFC8288"/> apply, as do th ose of the
discovery specifications <xref target="RFC6690"/>, <xref target="RFC7252"/>, and <xref target="RFC9176"/>.</t> discovery specifications <xref target="RFC6690"/>, <xref target="RFC7252"/>, and <xref target="RFC9176"/>.</t>
</section> </section>
</middle> </middle>
<back> <back>
<references> <references>
<name>References</name> <name>References</name>
<references anchor="sec-normative-references"> <references anchor="sec-normative-references">
<name>Normative References</name> <name>Normative References</name>
<reference anchor="RFC8288">
<front> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8288.xml"
<title>Web Linking</title> />
<author fullname="M. Nottingham" initials="M." surname="Nottingham"/
> <referencegroup anchor="BCP26" target="https://www.rfc-editor.org/info/bcp26">
<date month="October" year="2017"/> <xi:include
<abstract> href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8126.xml"/>
<t>This specification defines a model for the relationships betwee </referencegroup>
n resources on the Web ("links") and the type of those relationships ("link rela <referencegroup anchor="STD80" target="https://www.rfc-editor.org/info/std80">
tion types").</t> <xi:include
<t>It also defines the serialisation of such links in HTTP headers href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.0020.xml"/>
with the Link header field.</t> </referencegroup>
</abstract>
</front> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"
<seriesInfo name="RFC" value="8288"/> />
<seriesInfo name="DOI" value="10.17487/RFC8288"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"
</reference> />
<reference anchor="BCP26">
<front>
<title>Guidelines for Writing an IANA Considerations Section in RFCs
</title>
<author fullname="M. Cotton" initials="M." surname="Cotton"/>
<author fullname="B. Leiba" initials="B." surname="Leiba"/>
<author fullname="T. Narten" initials="T." surname="Narten"/>
<date month="June" year="2017"/>
<abstract>
<t>Many protocols make use of points of extensibility that use con
stants to identify various protocol parameters. To ensure that the values in the
se fields do not have conflicting uses and to promote interoperability, their al
locations are often coordinated by a central record keeper. For IETF protocols,
that role is filled by the Internet Assigned Numbers Authority (IANA).</t>
<t>To make assignments in a given registry prudently, guidance des
cribing the conditions under which new values should be assigned, as well as whe
n and how modifications to existing values can be made, is needed. This document
defines a framework for the documentation of these guidelines by specification
authors, in order to assure that the provided guidance for the IANA Consideratio
ns is clear and addresses the various issues that are likely in the operation of
a registry.</t>
<t>This is the third edition of this document; it obsoletes RFC 52
26.</t>
</abstract>
</front>
<seriesInfo name="BCP" value="26"/>
<seriesInfo name="RFC" value="8126"/>
<seriesInfo name="DOI" value="10.17487/RFC8126"/>
</reference>
<reference anchor="STD80">
<front>
<title>ASCII format for network interchange</title>
<author fullname="V.G. Cerf" initials="V.G." surname="Cerf"/>
<date month="October" year="1969"/>
</front>
<seriesInfo name="STD" value="80"/>
<seriesInfo name="RFC" value="20"/>
<seriesInfo name="DOI" value="10.17487/RFC0020"/>
</reference>
<reference anchor="RFC2119">
<front>
<title>Key words for use in RFCs to Indicate Requirement Levels</tit
le>
<author fullname="S. Bradner" initials="S." surname="Bradner"/>
<date month="March" year="1997"/>
<abstract>
<t>In many standards track documents several words are used to sig
nify the requirements in the specification. These words are often capitalized. T
his document defines these words as they should be interpreted in IETF documents
. This document specifies an Internet Best Current Practices for the Internet Co
mmunity, and requests discussion and suggestions for improvements.</t>
</abstract>
</front>
<seriesInfo name="BCP" value="14"/>
<seriesInfo name="RFC" value="2119"/>
<seriesInfo name="DOI" value="10.17487/RFC2119"/>
</reference>
<reference anchor="RFC8174">
<front>
<title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</ti
tle>
<author fullname="B. Leiba" initials="B." surname="Leiba"/>
<date month="May" year="2017"/>
<abstract>
<t>RFC 2119 specifies common key words that may be used in protoco
l specifications. This document aims to reduce the ambiguity by clarifying that
only UPPERCASE usage of the key words have the defined special meanings.</t>
</abstract>
</front>
<seriesInfo name="BCP" value="14"/>
<seriesInfo name="RFC" value="8174"/>
<seriesInfo name="DOI" value="10.17487/RFC8174"/>
</reference>
<reference anchor="IANA.core-parameters" target="https://www.iana.org/as signments/core-parameters"> <reference anchor="IANA.core-parameters" target="https://www.iana.org/as signments/core-parameters">
<front> <front>
<title>Constrained RESTful Environments (CoRE) Parameters</title> <title>Constrained RESTful Environments (CoRE) Parameters</title>
<author> <author>
<organization>IANA</organization> <organization>IANA</organization>
</author> </author>
</front> </front>
</reference> </reference>
</references> </references>
<references anchor="sec-informative-references"> <references anchor="sec-informative-references">
<name>Informative References</name> <name>Informative References</name>
<reference anchor="RFC6690">
<front> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6690.xml"
<title>Constrained RESTful Environments (CoRE) Link Format</title> />
<author fullname="Z. Shelby" initials="Z." surname="Shelby"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7252.xml"
<date month="August" year="2012"/> />
<abstract> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7641.xml"
<t>This specification defines Web Linking using a link format for />
use by constrained web servers to describe hosted resources, their attributes, a <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8075.xml"
nd other relationships between links. Based on the HTTP Link Header field define />
d in RFC 5988, the Constrained RESTful Environments (CoRE) Link Format is carrie <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8613.xml"
d as a payload and is assigned an Internet media type. "RESTful" refers to the R />
epresentational State Transfer (REST) architecture. A well-known URI is defined <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.5988.xml"
as a default entry point for requesting the links hosted by a server. [STANDARDS />
-TRACK]</t> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9176.xml"
</abstract> />
</front>
<seriesInfo name="RFC" value="6690"/>
<seriesInfo name="DOI" value="10.17487/RFC6690"/>
</reference>
<reference anchor="RFC7252">
<front>
<title>The Constrained Application Protocol (CoAP)</title>
<author fullname="Z. Shelby" initials="Z." surname="Shelby"/>
<author fullname="K. Hartke" initials="K." surname="Hartke"/>
<author fullname="C. Bormann" initials="C." surname="Bormann"/>
<date month="June" year="2014"/>
<abstract>
<t>The Constrained Application Protocol (CoAP) is a specialized we
b transfer protocol for use with constrained nodes and constrained (e.g., low-po
wer, lossy) networks. The nodes often have 8-bit microcontrollers with small amo
unts of ROM and RAM, while constrained networks such as IPv6 over Low-Power Wire
less Personal Area Networks (6LoWPANs) often have high packet error rates and a
typical throughput of 10s of kbit/s. The protocol is designed for machine- to-ma
chine (M2M) applications such as smart energy and building automation.</t>
<t>CoAP provides a request/response interaction model between appl
ication endpoints, supports built-in discovery of services and resources, and in
cludes key concepts of the Web such as URIs and Internet media types. CoAP is de
signed to easily interface with HTTP for integration with the Web while meeting
specialized requirements such as multicast support, very low overhead, and simpl
icity for constrained environments.</t>
</abstract>
</front>
<seriesInfo name="RFC" value="7252"/>
<seriesInfo name="DOI" value="10.17487/RFC7252"/>
</reference>
<reference anchor="RFC7641">
<front>
<title>Observing Resources in the Constrained Application Protocol (
CoAP)</title>
<author fullname="K. Hartke" initials="K." surname="Hartke"/>
<date month="September" year="2015"/>
<abstract>
<t>The Constrained Application Protocol (CoAP) is a RESTful applic
ation protocol for constrained nodes and networks. The state of a resource on a
CoAP server can change over time. This document specifies a simple protocol exte
nsion for CoAP that enables CoAP clients to "observe" resources, i.e., to retrie
ve a representation of a resource and keep this representation updated by the se
rver over a period of time. The protocol follows a best-effort approach for send
ing new representations to clients and provides eventual consistency between the
state observed by each client and the actual resource state at the server.</t>
</abstract>
</front>
<seriesInfo name="RFC" value="7641"/>
<seriesInfo name="DOI" value="10.17487/RFC7641"/>
</reference>
<reference anchor="RFC8075">
<front>
<title>Guidelines for Mapping Implementations: HTTP to the Constrain
ed Application Protocol (CoAP)</title>
<author fullname="A. Castellani" initials="A." surname="Castellani"/
>
<author fullname="S. Loreto" initials="S." surname="Loreto"/>
<author fullname="A. Rahman" initials="A." surname="Rahman"/>
<author fullname="T. Fossati" initials="T." surname="Fossati"/>
<author fullname="E. Dijk" initials="E." surname="Dijk"/>
<date month="February" year="2017"/>
<abstract>
<t>This document provides reference information for implementing a
cross-protocol network proxy that performs translation from the HTTP protocol t
o the Constrained Application Protocol (CoAP). This will enable an HTTP client t
o access resources on a CoAP server through the proxy. This document describes h
ow an HTTP request is mapped to a CoAP request and how a CoAP response is mapped
back to an HTTP response. This includes guidelines for status code, URI, and me
dia type mappings, as well as additional interworking advice.</t>
</abstract>
</front>
<seriesInfo name="RFC" value="8075"/>
<seriesInfo name="DOI" value="10.17487/RFC8075"/>
</reference>
<reference anchor="RFC8613">
<front>
<title>Object Security for Constrained RESTful Environments (OSCORE)
</title>
<author fullname="G. Selander" initials="G." surname="Selander"/>
<author fullname="J. Mattsson" initials="J." surname="Mattsson"/>
<author fullname="F. Palombini" initials="F." surname="Palombini"/>
<author fullname="L. Seitz" initials="L." surname="Seitz"/>
<date month="July" year="2019"/>
<abstract>
<t>This document defines Object Security for Constrained RESTful E
nvironments (OSCORE), a method for application-layer protection of the Constrain
ed Application Protocol (CoAP), using CBOR Object Signing and Encryption (COSE).
OSCORE provides end-to-end protection between endpoints communicating using CoA
P or CoAP-mappable HTTP. OSCORE is designed for constrained nodes and networks s
upporting a range of proxy operations, including translation between different t
ransport protocols.</t>
<t>Although an optional functionality of CoAP, OSCORE alters CoAP
options processing and IANA registration. Therefore, this document updates RFC 7
252.</t>
</abstract>
</front>
<seriesInfo name="RFC" value="8613"/>
<seriesInfo name="DOI" value="10.17487/RFC8613"/>
</reference>
<reference anchor="RFC5988">
<front>
<title>Web Linking</title>
<author fullname="M. Nottingham" initials="M." surname="Nottingham"/
>
<date month="October" year="2010"/>
<abstract>
<t>This document specifies relation types for Web links, and defin
es a registry for them. It also defines the use of such links in HTTP headers wi
th the Link header field. [STANDARDS-TRACK]</t>
</abstract>
</front>
<seriesInfo name="RFC" value="5988"/>
<seriesInfo name="DOI" value="10.17487/RFC5988"/>
</reference>
<reference anchor="RFC9176">
<front>
<title>Constrained RESTful Environments (CoRE) Resource Directory</t
itle>
<author fullname="C. Amsüss" initials="C." role="editor" surname="Am
süss"/>
<author fullname="Z. Shelby" initials="Z." surname="Shelby"/>
<author fullname="M. Koster" initials="M." surname="Koster"/>
<author fullname="C. Bormann" initials="C." surname="Bormann"/>
<author fullname="P. van der Stok" initials="P." surname="van der St
ok"/>
<date month="April" year="2022"/>
<abstract>
<t>In many Internet of Things (IoT) applications, direct discovery
of resources is not practical due to sleeping nodes or networks where multicast
traffic is inefficient. These problems can be solved by employing an entity cal
led a Resource Directory (RD), which contains information about resources held o
n other servers, allowing lookups to be performed for those resources. The input
to an RD is composed of links, and the output is composed of links constructed
from the information stored in the RD. This document specifies the web interface
s that an RD supports for web servers to discover the RD and to register, mainta
in, look up, and remove information on resources. Furthermore, new target attrib
utes useful in conjunction with an RD are defined.</t>
</abstract>
</front>
<seriesInfo name="RFC" value="9176"/>
<seriesInfo name="DOI" value="10.17487/RFC9176"/>
</reference>
</references> </references>
</references> </references>
<?line 232?>
<section numbered="false" anchor="acknowledgements"> <section numbered="false" anchor="acknowledgements">
<name>Acknowledgements</name> <name>Acknowledgements</name>
<t>The CoRE WG had been discussing setting up a registry for target <t>The CoRE Working Group had been discussing setting up a registry for ta rget
attributes since the final touches were made on <xref target="RFC6690"/>. attributes since the final touches were made on <xref target="RFC6690"/>.
The update of the Web Linking specification to <xref target="RFC8288"/> provided the The update of the Web Linking specification to <xref target="RFC8288"/> provided the
formal setting, but it took until <contact fullname="Jaime Jiménez"/> provided t he set of formal setting, but it took until <contact fullname="Jaime Jiménez"/> provided t he set of
initial registrations to generate a first version of this specification. initial registrations to generate a first draft version of this specification.
The current version addresses additional input and working group last The current document addresses additional input and Working Group Last
call comments by Call comments by
<contact fullname="Esko Dijk"/>, <contact fullname="Esko Dijk"/>,
<contact fullname="Marco Tiloca"/>, <contact fullname="Marco Tiloca"/>,
<contact fullname="Thomas Fossati"/>, <contact fullname="Thomas Fossati"/>,
and and
<contact fullname="Mohamed Boucadair"/>, <contact fullname="Mohamed Boucadair"/>,
as well as area director review comments from as well as Area Director review comments from
<contact fullname="Rob Wilton"/>.</t> <contact fullname="Rob Wilton"/>.</t>
</section> </section>
<section anchor="contributors" numbered="false" toc="include" removeInRFC="f alse"> <section anchor="contributors" numbered="false" toc="include" removeInRFC="f alse">
<name>Contributors</name> <name>Contributors</name>
<contact initials="J." surname="Jiménez" fullname="Jaime Jiménez"> <contact initials="J." surname="Jiménez" fullname="Jaime Jiménez">
<organization>Ericsson</organization> <organization>Ericsson</organization>
<address> <address>
<email>jaime@iki.fi</email> <email>jaime@iki.fi</email>
</address> </address>
</contact> </contact>
<t>Jaime provided the list of initial registrations.</t> <t>Jaime provided the list of initial registrations.</t>
</section> </section>
</back> </back>
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 End of changes. 42 change blocks. 
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