§18 IANA Considerations RFC 9110

The change controller for the following registrations is: "IETF ([email protected]) - Internet Engineering Task Force".

IANA has updated the "Uniform Resource Identifier (URI) Schemes" registry BCP35 at with the permanent schemes listed in Table 2 in Section 4.2.

IANA has updated the "Hypertext Transfer Protocol (HTTP) Method Registry" at with the registration procedure of Section 16.1.1 and the method names summarized in the following table.

Method  |  Safe  |  Idempotent  |  Section
CONNECT  |  no  |  no  |  9.3.6
DELETE  |  no  |  yes  |  9.3.5
GET  |  yes  |  yes  |  9.3.1
HEAD  |  yes  |  yes  |  9.3.2
OPTIONS  |  yes  |  yes  |  9.3.7
POST  |  no  |  no  |  9.3.3
PUT  |  no  |  yes  |  9.3.4
TRACE  |  yes  |  yes  |  9.3.8
*  |  no  |  no  |  18.2

The method name "*" is reserved because using "*" as a method name would conflict with its usage as a wildcard in some fields (e.g., "Access-Control-Request-Method").

IANA has updated the "Hypertext Transfer Protocol (HTTP) Status Code Registry" at with the registration procedure of Section 16.2.1 and the status code values summarized in the following table.

Value  |  Description  |  Section
100  |  Continue  |  15.2.1
101  |  Switching Protocols  |  15.2.2
200  |  OK  |  15.3.1
201  |  Created  |  15.3.2
202  |  Accepted  |  15.3.3
203  |  Non-Authoritative Information  |  15.3.4
204  |  No Content  |  15.3.5
205  |  Reset Content  |  15.3.6
206  |  Partial Content  |  15.3.7
300  |  Multiple Choices  |  15.4.1
301  |  Moved Permanently  |  15.4.2
302  |  Found  |  15.4.3
303  |  See Other  |  15.4.4
304  |  Not Modified  |  15.4.5
305  |  Use Proxy  |  15.4.6
306  |  (Unused)  |  15.4.7
307  |  Temporary Redirect  |  15.4.8
308  |  Permanent Redirect  |  15.4.9
400  |  Bad Request  |  15.5.1
401  |  Unauthorized  |  15.5.2
402  |  Payment Required  |  15.5.3
403  |  Forbidden  |  15.5.4
404  |  Not Found  |  15.5.5
405  |  Method Not Allowed  |  15.5.6
406  |  Not Acceptable  |  15.5.7
407  |  Proxy Authentication Required  |  15.5.8
408  |  Request Timeout  |  15.5.9
409  |  Conflict  |  15.5.10
410  |  Gone  |  15.5.11
411  |  Length Required  |  15.5.12
412  |  Precondition Failed  |  15.5.13
413  |  Content Too Large  |  15.5.14
414  |  URI Too Long  |  15.5.15
415  |  Unsupported Media Type  |  15.5.16
416  |  Range Not Satisfiable  |  15.5.17
417  |  Expectation Failed  |  15.5.18
418  |  (Unused)  |  15.5.19
421  |  Misdirected Request  |  15.5.20
422  |  Unprocessable Content  |  15.5.21
426  |  Upgrade Required  |  15.5.22
500  |  Internal Server Error  |  15.6.1
501  |  Not Implemented  |  15.6.2
502  |  Bad Gateway  |  15.6.3
503  |  Service Unavailable  |  15.6.4
504  |  Gateway Timeout  |  15.6.5
505  |  HTTP Version Not Supported  |  15.6.6

This specification updates the HTTP-related aspects of the existing registration procedures for message header fields defined in RFC3864. It replaces the old procedures as they relate to HTTP by defining a new registration procedure and moving HTTP field definitions into a separate registry.

IANA has created a new registry titled "Hypertext Transfer Protocol (HTTP) Field Name Registry" as outlined in Section 16.3.1.

IANA has moved all entries in the "Permanent Message Header Field Names" and "Provisional Message Header Field Names" registries (see ) with the protocol 'http' to this registry and has applied the following changes:

The 'Applicable Protocol' field has been omitted.

Entries that had a status of 'standard', 'experimental', 'reserved', or 'informational' have been made to have a status of 'permanent'.

Provisional entries without a status have been made to have a status of 'provisional'.

Permanent entries without a status (after confirmation that the registration document did not define one) have been made to have a status of 'provisional'. The expert(s) can choose to update the entries' status if there is evidence that another is more appropriate.

IANA has annotated the "Permanent Message Header Field Names" and "Provisional Message Header Field Names" registries with the following note to indicate that HTTP field name registrations have moved:

Note HTTP field name registrations have been moved to [] per [RFC9110].

IANA has updated the "Hypertext Transfer Protocol (HTTP) Field Name Registry" with the field names listed in the following table.

Field Name  |  Status  |  Section  |  Comments
Accept  |  permanent  |  12.5.1  |  
Accept-Charset  |  deprecated  |  12.5.2  |  
Accept-Encoding  |  permanent  |  12.5.3  |  
Accept-Language  |  permanent  |  12.5.4  |  
Accept-Ranges  |  permanent  |  14.3  |  
Allow  |  permanent  |  10.2.1  |  
Authentication-Info  |  permanent  |  11.6.3  |  
Authorization  |  permanent  |  11.6.2  |  
Connection  |  permanent  |  7.6.1  |  
Content-Encoding  |  permanent  |  8.4  |  
Content-Language  |  permanent  |  8.5  |  
Content-Length  |  permanent  |  8.6  |  
Content-Location  |  permanent  |  8.7  |  
Content-Range  |  permanent  |  14.4  |  
Content-Type  |  permanent  |  8.3  |  
Date  |  permanent  |  6.6.1  |  
ETag  |  permanent  |  8.8.3  |  
Expect  |  permanent  |  10.1.1  |  
From  |  permanent  |  10.1.2  |  
Host  |  permanent  |  7.2  |  
If-Match  |  permanent  |  13.1.1  |  
If-Modified-Since  |  permanent  |  13.1.3  |  
If-None-Match  |  permanent  |  13.1.2  |  
If-Range  |  permanent  |  13.1.5  |  
If-Unmodified-Since  |  permanent  |  13.1.4  |  
Last-Modified  |  permanent  |  8.8.2  |  
Location  |  permanent  |  10.2.2  |  
Max-Forwards  |  permanent  |  7.6.2  |  
Proxy-Authenticate  |  permanent  |  11.7.1  |  
Proxy-Authentication-Info  |  permanent  |  11.7.3  |  
Proxy-Authorization  |  permanent  |  11.7.2  |  
Range  |  permanent  |  14.2  |  
Referer  |  permanent  |  10.1.3  |  
Retry-After  |  permanent  |  10.2.3  |  
Server  |  permanent  |  10.2.4  |  
TE  |  permanent  |  10.1.4  |  
Trailer  |  permanent  |  6.6.2  |  
Upgrade  |  permanent  |  7.8  |  
User-Agent  |  permanent  |  10.1.5  |  
Vary  |  permanent  |  12.5.5  |  
Via  |  permanent  |  7.6.3  |  
WWW-Authenticate  |  permanent  |  11.6.1  |  
*  |  permanent  |  12.5.5  |  (reserved)

The field name "*" is reserved because using that name as an HTTP header field might conflict with its special semantics in the Vary header field (Section 12.5.5).

IANA has updated the "Content-MD5" entry in the new registry to have a status of 'obsoleted' with references to RFC2616 (for the definition of the header field) and RFC7231 (which removed the field definition from the updated specification).

IANA has updated the "Hypertext Transfer Protocol (HTTP) Authentication Scheme Registry" at with the registration procedure of Section 16.4.1. No authentication schemes are defined in this document.

IANA has updated the "HTTP Content Coding Registry" at with the registration procedure of Section 16.6.1 and the content coding names summarized in the table below.

Name  |  Description  |  Section
compress  |  UNIX "compress" data format Welch  |  8.4.1.1
deflate  |  "deflate" compressed data (RFC1951) inside the "zlib" data format (RFC1950)  |  8.4.1.2
gzip  |  GZIP file format RFC1952  |  8.4.1.3
identity  |  Reserved  |  12.5.3
x-compress  |  Deprecated (alias for compress)  |  8.4.1.1
x-gzip  |  Deprecated (alias for gzip)  |  8.4.1.3

IANA has updated the "HTTP Range Unit Registry" at with the registration procedure of Section 16.5.1 and the range unit names summarized in the table below.

Range Unit Name  |  Description  |  Section
bytes  |  a range of octets  |  14.1.2
none  |  reserved as keyword to indicate range requests are not supported  |  14.3

IANA has updated the "Media Types" registry at with the registration information in Section 14.6 for the media type "multipart/byteranges".

IANA has updated the registry note about "q" parameters with a link to Section 12.5.1 of this document.

IANA has updated the "Service Name and Transport Protocol Port Number Registry" at for the services on ports 80 and 443 that use UDP or TCP to:

use this document as "Reference", and

when currently unspecified, set "Assignee" to "IESG" and "Contact" to "IETF_Chair".

IANA has updated the "Hypertext Transfer Protocol (HTTP) Upgrade Token Registry" at with the registration procedure described in Section 16.7 and the upgrade token names summarized in the following table.

Name  |  Description  |  Expected Version Tokens  |  Section
HTTP  |  Hypertext Transfer Protocol  |  any DIGIT.DIGIT (e.g., "2.0")  |  2.5