Internet Assigned Numbers Authority

Constrained RESTful Environments (CoRE) Parameters

Created
2012-06-08
Last Updated
2024-03-01
Available Formats

XML

HTML

Plain text

Registries included below

Resource Type (rt=) Link Target Attribute Values

Expert(s)
Carsten Bormann, Jaime Jimenez, Christian Amsüss
Reference
[RFC6690]
Note
Registration requests should be sent to the mailing list described in 
[RFC6690]. If approved, designated experts should notify IANA within 
two weeks. For assistance, please contact iana@iana.org.
    
Available Formats

CSV

Interface Description (if=) Link Target Attribute Values

Expert(s)
Carsten Bormann, Jaime Jimenez, Christian Amsüss
Reference
[RFC6690]
Note
Registration requests should be sent to the mailing list described in 
[RFC6690]. If approved, designated experts should notify IANA within 
two weeks. For assistance, please contact iana@iana.org.
    
Available Formats

CSV

CoAP Codes

Registration Procedure(s)
Reserved ranges may be allocated in accordance with section 4.3 of [RFC8126].
Reference
[RFC7252, Section 12.1]
Available Formats

CSV
Code Description Reference
0.00 Indicates an Empty message. [RFC7252, section 4.1]
0.01-0.31 Indicates a request. Values in this range are assigned by the [CoAP Method Codes] sub-registry. [RFC7252, section 12.1.1]
1.00-1.31 Reserved [RFC7252]
2.00-5.31 Indicates a response. Values in this range are assigned by the [CoAP Response Codes] sub-registry. [RFC7252, section 12.1.2]
6.00-7.31 Reserved [RFC7252]

CoAP Method Codes

Registration Procedure(s)
IETF Review or IESG Approval
Reference
[RFC7252, Section 12.1.1]
Available Formats

CSV
Code Name Reference
0.01 GET [RFC7252]
0.02 POST [RFC7252]
0.03 PUT [RFC7252]
0.04 DELETE [RFC7252]
0.05 FETCH [RFC8132]
0.06 PATCH [RFC8132]
0.07 iPATCH [RFC8132]
0.08-0.31 Unassigned

CoAP Response Codes

Registration Procedure(s)
IETF Review or IESG Approval
Reference
[RFC7252, Section 12.1.2]
Available Formats

CSV
Code Description Reference
2.00 Unassigned
2.01 Created [RFC7252]
2.02 Deleted [RFC7252]
2.03 Valid [RFC7252]
2.04 Changed [RFC7252]
2.05 Content [RFC7252]
2.06-2.30 Unassigned
2.31 Continue [RFC7959]
3.00-3.31 Reserved [RFC7252]
4.00 Bad Request [RFC7252]
4.01 Unauthorized [RFC7252]
4.02 Bad Option [RFC7252]
4.03 Forbidden [RFC7252]
4.04 Not Found [RFC7252]
4.05 Method Not Allowed [RFC7252]
4.06 Not Acceptable [RFC7252]
4.07 Unassigned
4.08 Request Entity Incomplete [RFC7959]
4.09 Conflict [RFC8132]
4.10-4.11 Unassigned
4.12 Precondition Failed [RFC7252]
4.13 Request Entity Too Large [RFC7252][RFC7959]
4.14 Unassigned
4.15 Unsupported Content-Format [RFC7252]
4.16-4.21 Unassigned
4.22 Unprocessable Entity [RFC8132]
4.23-4.28 Unassigned
4.29 Too Many Requests [RFC8516]
4.30-4.31 Unassigned
5.00 Internal Server Error [RFC7252]
5.01 Not Implemented [RFC7252]
5.02 Bad Gateway [RFC7252]
5.03 Service Unavailable [RFC7252]
5.04 Gateway Timeout [RFC7252]
5.05 Proxying Not Supported [RFC7252]
5.06-5.07 Unassigned
5.08 Hop Limit Reached [RFC8768]
5.09-5.31 Unassigned

CoAP Option Numbers

Expert(s)
Bilhanan Silverajan (primary), Klaus Hartke (secondary), Carsten Bormann (secondary), Jaime Jimenez (secondary), Alexander Pelov (secondary)
Reference
[RFC7252, Section 12.2]
Available Formats

CSV
Range Registration Procedures
0-255 IETF Review or IESG Approval
256-2047 Specification Required
2048-64999 Expert Review
65000-65535 Experimental use (no operational use)
Number Name Reference
0 Reserved [RFC7252]
1 If-Match [RFC7252][RFC8613]
2 Unassigned
3 Uri-Host [RFC7252][RFC8613]
4 ETag [RFC7252][RFC8613]
5 If-None-Match [RFC7252][RFC8613]
6 Observe [RFC7641][RFC8613]
7 Uri-Port [RFC7252][RFC8613]
8 Location-Path [RFC7252][RFC8613]
9 OSCORE [RFC8613]
10 Unassigned
11 Uri-Path [RFC7252][RFC8613]
12 Content-Format [RFC7252][RFC8613]
13 Unassigned
14 Max-Age [RFC7252][RFC8516][RFC8613]
15 Uri-Query [RFC7252][RFC8613]
16 Hop-Limit [RFC8768]
17 Accept [RFC7252][RFC8613]
18 Unassigned
19 Q-Block1 [RFC9177]
20 Location-Query [RFC7252][RFC8613]
21 EDHOC (TEMPORARY - registered 2021-11-08, extension registered 2023-09-25, expires 2024-11-08) [draft-ietf-core-oscore-edhoc-08]
22 Unassigned
23 Block2 [RFC7959][RFC8323][RFC8613]
24-26 Unassigned
27 Block1 [RFC7959][RFC8323][RFC8613]
28 Size2 [RFC7959][RFC8613]
29-30 Unassigned
31 Q-Block2 [RFC9177]
32-34 Unassigned
35 Proxy-Uri [RFC7252][RFC8613]
36-38 Unassigned
39 Proxy-Scheme [RFC7252][RFC8613]
40-59 Unassigned
60 Size1 [RFC7252][RFC8613]
61-127 Unassigned
128 Reserved [RFC7252]
129-131 Unassigned
132 Reserved [RFC7252]
133-135 Unassigned
136 Reserved [RFC7252]
137-139 Unassigned
140 Reserved [RFC7252]
141-251 Unassigned
252 Echo [RFC9175]
253-257 Unassigned
258 No-Response [RFC7967][RFC8613]
259-291 Unassigned
292 Request-Tag [RFC9175]
293-2048 Unassigned
2049 OCF-Accept-Content-Format-Version [Michael_Koster]
2050-2052 Unassigned
2053 OCF-Content-Format-Version [Michael_Koster]
2054-64999 Unassigned
65000-65535 Reserved for Experimental Use [RFC7252]

CoAP Content-Formats

Expert(s)
Esko Dijk (primary), Klaus Hartke (secondary), Carsten Bormann (secondary), Jaime Jimenez (secondary), Alexander Pelov (secondary)
Reference
[RFC7252, Section 12.3][RFC Errata 4954]
Available Formats

CSV
Range Registration Procedures
0-255 Expert Review
256-9999 IETF Review or IESG Approval
10000-64999 First Come First Served
65000-65535 Experimental use (no operational use)
Content Type Content Coding ID Reference
text/plain; charset=utf-8 0 [RFC2046][RFC3676][RFC5147]
Unassigned 1-15
application/cose; cose-type="cose-encrypt0" 16 [RFC9052]
application/cose; cose-type="cose-mac0" 17 [RFC9052]
application/cose; cose-type="cose-sign1" 18 [RFC9052]
application/ace+cbor 19 [RFC9200]
Unassigned 20
image/gif 21 [https://www.w3.org/Graphics/GIF/spec-gif89a.txt]
image/jpeg 22 [ISO/IEC 10918-5]
image/png 23 [RFC2083]
Unassigned 24-39
application/link-format 40 [RFC6690]
application/xml 41 [RFC3023]
application/octet-stream 42 [RFC2045][RFC2046]
Unassigned 43-46
application/exi 47 ["Efficient XML Interchange (EXI) Format 1.0 (Second Edition)", February 2014]
Unassigned 48-49
application/json 50 [RFC8259]
application/json-patch+json 51 [RFC6902]
application/merge-patch+json 52 [RFC7396]
Unassigned 53-59
application/cbor 60 [RFC8949]
application/cwt 61 [RFC8392]
application/multipart-core 62 [RFC8710]
application/cbor-seq 63 [RFC8742]
application/edhoc+cbor-seq 64 [RFC-ietf-lake-edhoc-22]
application/cid-edhoc+cbor-seq 65 [RFC-ietf-lake-edhoc-22]
Unassigned 66-95
application/cose; cose-type="cose-encrypt" 96 [RFC9052]
application/cose; cose-type="cose-mac" 97 [RFC9052]
application/cose; cose-type="cose-sign" 98 [RFC9052]
Unassigned 99-100
application/cose-key 101 [RFC9052]
application/cose-key-set 102 [RFC9052]
Unassigned 103-109
application/senml+json 110 [RFC8428]
application/sensml+json 111 [RFC8428]
application/senml+cbor 112 [RFC8428]
application/sensml+cbor 113 [RFC8428]
application/senml-exi 114 [RFC8428]
application/sensml-exi 115 [RFC8428]
Unassigned 116-139
application/yang-data+cbor; id=sid 140 [RFC9254]
Unassigned 141-255
application/coap-group+json 256 [RFC7390]
application/concise-problem-details+cbor 257 [RFC9290]
application/swid+cbor 258 [RFC9393]
application/pkixcmp 259 [RFC9482][RFC4210]
application/yang-sid+json 260 [RFC-ietf-core-sid-24]
Unassigned 261-270
application/dots+cbor 271 [RFC9132]
application/missing-blocks+cbor-seq 272 [RFC9177]
Unassigned 273-279
application/pkcs7-mime; smime-type=server-generated-key 280 [RFC7030][RFC8551][RFC9148]
application/pkcs7-mime; smime-type=certs-only 281 [RFC8551][RFC9148]
Unassigned 282-283
application/pkcs8 284 [RFC5958][RFC8551][RFC9148]
application/csrattrs 285 [RFC7030][RFC9148]
application/pkcs10 286 [RFC5967][RFC8551][RFC9148]
application/pkix-cert 287 [RFC2585][RFC9148]
Unassigned 288-289
application/aif+cbor 290 [RFC9237]
application/aif+json 291 [RFC9237]
Unassigned 292-309
application/senml+xml 310 [RFC8428]
application/sensml+xml 311 [RFC8428]
Unassigned 312-319
application/senml-etch+json 320 [RFC8790]
Unassigned 321
application/senml-etch+cbor 322 [RFC8790]
Unassigned 323-339
application/yang-data+cbor 340 [RFC9254]
application/yang-data+cbor; id=name 341 [RFC9254]
Unassigned 342-431
application/td+json 432 ["Web of Things (WoT) Thing Description 1.1", April 2022]
application/tm+json 433 ["Web of Things (WoT) Thing Description 1.1", April 2022]
Unassigned 434-835
application/voucher+cose (TEMPORARY - registered 2022-04-12, extension registered 2024-03-01, expires 2025-04-12) 836 [draft-ietf-anima-constrained-voucher-23]
Unassigned 837-1541
Reserved, do not use 1542-1543 [OMA-TS-LightweightM2M-V1_0]
Unassigned 1544-9999
application/vnd.ocf+cbor 10000 [Michael_Koster]
application/oscore 10001 [RFC8613]
application/javascript 10002 [RFC4329]
Unassigned 10003-11049
application/json deflate 11050 [RFC8259][RFC9110, Section 8.4.1.2]
Unassigned 11051-11059
application/cbor deflate 11060 [RFC8949][RFC9110, Section 8.4.1.2]
Unassigned 11061-11541
application/vnd.oma.lwm2m+tlv 11542 [OMA-TS-LightweightM2M-V1_0]
application/vnd.oma.lwm2m+json 11543 [OMA-TS-LightweightM2M-V1_0]
application/vnd.oma.lwm2m+cbor 11544 [OMA-TS-LightweightM2M-V1_2]
Unassigned 11545-19999
text/css 20000 [RFC2318]
Unassigned 20001-29999
image/svg+xml 30000 [https://www.w3.org/TR/SVG/mimereg.html]
Unassigned 30001-64999
Reserved for Experimental Use 65000-65535 [RFC7252]

CoAP Signaling Codes

Registration Procedure(s)
IETF Review or IESG Approval
Reference
[RFC8323]
Available Formats

CSV
Code Name Reference
7.00 Unassigned
7.01 CSM [RFC8323]
7.02 Ping [RFC8323]
7.03 Pong [RFC8323]
7.04 Release [RFC8323]
7.05 Abort [RFC8323]
7.06-7.31 Unassigned

CoAP Signaling Option Numbers

Expert(s)
Bilhanan Silverajan (primary), Klaus Hartke (secondary), Alexander Pelov (secondary)
Reference
[RFC8323]
Available Formats

CSV
Range Registration Procedures Note
0-255 IETF Review or IESG Approval Range applies to Option Number field
256-2047 Specification Required Range applies to Option Number field
2048-64999 Expert Review Range applies to Option Number field
65000-65535 Experimental use (no operational use) Range applies to Option Number field
Applies to Number Name Reference
7.01 2 Max-Message-Size [RFC8323]
7.01 4 Block-Wise-Transfer [RFC8323]
7.01 6 Extended-Token-Length [RFC8974]
7.02, 7.03 2 Custody [RFC8323]
7.04 2 Alternative-Address [RFC8323]
7.04 4 Hold-Off [RFC8323]
7.05 2 Bad-CSM-Option [RFC8323]
7.xx (all) 9 OSCORE [RFC8613]

OSCORE Flag Bits

Registration Procedure(s)
Expert Review
Expert(s)
Francesca Palombini, Göran Selander, Christian Amsüss
Reference
[RFC8613]
Available Formats

CSV
Bit Position Name Description Reference
0 Reserved [RFC8613]
1 Reserved [RFC8613]
2 Group Flag For using a Group OSCORE Security Context, set to 1 if the message is protected with the group mode [draft-ietf-core-oscore-groupcomm-14]
3 Kid Context Flag Set to 1 if kid context is present in the compressed COSE object [RFC8613]
4 Kid Flag Set to 1 if kid is present in the compressed COSE object [RFC8613]
5-7 Partial IV Length Encodes the Partial IV length; can have value 0 to 5 [RFC8613]
8 Extension-2 Flag Set to 1 if the OSCORE Option specifies a third byte, which includes the flag bits 16-23 [draft-ietf-core-oscore-key-update-03]
9-14 Unassigned
15 Nonce Flag Set to 1 if nonce is present in the compressed COSE object [draft-ietf-core-oscore-key-update-03]
16 Extension-3 Flag Set to 1 if the OSCORE Option specifies a fourth byte, which includes the flag bits 24-31 [draft-ietf-core-oscore-key-update-03]
17-23 Unassigned
24 Extension-4 Flag Set to 1 if the OSCORE Option specifies a fifth byte, which includes the flag bits 32-39 [draft-ietf-core-oscore-key-update-03]
25-31 Unassigned
32 Extension-5 Flag Set to 1 if the OSCORE Option specifies a sixth byte, which includes the flag bits 40-47 [draft-ietf-core-oscore-key-update-03]
33-39 Unassigned
40 Extension-6 Flag Set to 1 if the OSCORE Option specifies a seventh byte, which includes the flag bits 48-55 [draft-ietf-core-oscore-key-update-03]
41-47 Unassigned
48 Extension-7 Flag Set to 1 if the OSCORE Option specifies a eighth byte, which includes the flag bits 56-63 [draft-ietf-core-oscore-key-update-03]
49-63 Unassigned

RD Parameters

Registration Procedure(s)
Expert Review
Expert(s)
Carsten Bormann, Jaime Jiménez, Christian Amsüss
Reference
[RFC9176]
Note
In accordance with [RFC-ietf-core-target-attr-06], all entries with the 
"A" flag set, including new ones, MUST also be registered in the 
"Target Attributes" registry [IANA registry core-parameters].
    
Available Formats

CSV
Name Short Validity Use Description Reference
Endpoint Name ep Unicode* RLA Name of the endpoint [RFC9176]
Lifetime lt 1-4294967295 R Lifetime of the registration in seconds [RFC9176]
Sector d Unicode* RLA Sector to which this endpoint belongs [RFC9176]
Registration Base URI base URI RLA The scheme, address, port, and path at which this server is available [RFC9176]
Page page Integer L Used for pagination [RFC9176]
Count count Integer L Used for pagination [RFC9176]
Endpoint Type et [RFC9176, Section 9.3.1] RLA Semantic type of the endpoint (see[RFC9176, Section 9.4]) [RFC9176]

Endpoint Type (et=) RD Parameter Values

Expert(s)
Carsten Bormann, Jaime Jiménez, Christian Amsüss
Reference
[RFC9176]
Available Formats

CSV
Range Registration Procedures
value starts with "core" IETF Review
all other values Specification Required
Value Description Reference Notes
core.rd-group An application group, as described in [RFC9176] Appendix A. [RFC9176]

Standard Problem Detail Keys

Registration Procedure(s)
Specification Required
Expert(s)
Thomas Fossati, Carsten Bormann
Reference
[RFC9290]
Available Formats

CSV
Key Value Name CDDL Type Brief Description Change Controller Reference
-1 title text / tag38 Short, human-readable summary of the problem shape IETF (core@ietf.org or art@ietf.org) [RFC9290]
-2 detail text / tag38 Human-readable explanation specific to this occurrence of the problem IETF (core@ietf.org or art@ietf.org) [RFC9290]
-3 instance ~uri URI reference identifying specific occurrence of the problem IETF (core@ietf.org or art@ietf.org) [RFC9290]
-4 response-code uint .size 1 CoAP response code IETF (core@ietf.org or art@ietf.org) [RFC9290]
-5 base-uri ~uri Base URI IETF (core@ietf.org or art@ietf.org) [RFC9290]
-6 base-lang tag38-ltag Base language tag (see [RFC9290, Appendix A]) IETF (core@ietf.org or art@ietf.org) [RFC9290]
-7 base-rtl tag38-direction Base writing direction (see [RFC9290, Appendix A]) IETF (core@ietf.org or art@ietf.org) [RFC9290]
-8 unprocessed-coap-option one-or-more<uint> Option number(s) of CoAP option(s) that were not understood IETF (core@ietf.org or art@ietf.org) [RFC9290, Section 3.1.1]
-25 request-body-error-position uint Byte index inside the request body at which the error became apparent [CoRE_WG] [draft-amsuess-core-pd-body-error-position-00]

Custom Problem Detail Keys

Registration Procedure(s)
Expert Review
Expert(s)
Thomas Fossati, Carsten Bormann
Reference
[RFC9290]
Available Formats

CSV
Key Value Name Brief Description Change Controller Reference
7807 tunnel-7807 Carry [RFC7807] problem details in a Concise Problem Details data item IETF (core@ietf.org or art@ietf.org) [RFC9290, Appendix B]

Target Attributes

Registration Procedure(s)
Expert Review
Expert(s)
Carsten Bormann, Marco Tiloca
Reference
[RFC-ietf-core-target-attr-06]
Available Formats

CSV
Attribute Name Brief Description Change Controller Reference
href reserved (not useful as target attribute name) IETF [RFC6690]
anchor reserved (not useful as target attribute name) IETF [RFC6690]
rel reserved (not useful as target attribute name) IETF [RFC6690]
rev reserved (not useful as target attribute name) IETF [RFC6690]
hreflang (Web Linking) IETF [RFC8288]
media (Web Linking) IETF [RFC8288]
title (Web Linking) IETF [RFC8288]
type (Web Linking) IETF [RFC8288]
rt resource type IETF [RFC6690, Section 3.1]
if interface description IETF [RFC6690, Section 3.2]
sz maximum size estimate IETF [RFC6690, Section 3.3]
ct Content-Format hint IETF [RFC7252, Section 7.2.1]
obs observable resource IETF [RFC7641, Section 6]
hct HTTP-CoAP URI mapping template IETF [RFC8075, Section 5.5]
osc hint: resource only accessible using OSCORE IETF [RFC8613, Section 9]
ep Endpoint Name (with rt="core.rd-ep") IETF [RFC9176, Section 9.3]
d Sector (with rt="core.rd-ep") IETF [RFC9176, Section 9.3]
base Registration Base URI (with rt="core.rd-ep") IETF [RFC9176, Section 9.3]
et Endpoint Type (with rt="core.rd-ep") IETF [RFC9176, Section 9.3]

Contact Information

ID Name Contact URI Last Updated
[CoRE_WG] IETF CoRE WG (reverts to IETF after WG closes) mailto:core&ietf.org
[Michael_Koster] Michael Koster mailto:michael.koster&smartthings.com 2017-07-03