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7. IANA Considerations

IANA has created two registries for new CBOR values. The registries are separate, that is, not under an umbrella registry, and follow the rules in [RFC5226]. IANA has also assigned a new MIME media type and an associated Constrained Application Protocol (CoAP) Content-Format entry.

7.1. Simple Values Registry​

IANA has created the "Concise Binary Object Representation (CBOR) Simple Values" registry. The initial values are shown in Table 2.

New entries in the range 0 to 19 are assigned by Standards Action. It is suggested that these Standards Actions allocate values starting with the number 16 in order to reserve the lower numbers for contiguous blocks (if any).

New entries in the range 32 to 255 are assigned by Specification Required.

7.2. Tags Registry​

IANA has created the "Concise Binary Object Representation (CBOR) Tags" registry. The initial values are shown in Table 3.

New entries in the range 0 to 23 are assigned by Standards Action. New entries in the range 24 to 255 are assigned by Specification Required. New entries in the range 256 to 18446744073709551615 are assigned by First Come First Served. The template for registration requests is:

  • Data item

  • Semantics (short form)

In addition, First Come First Served requests should include:

  • Point of contact

  • Description of semantics (URL) This description is optional; the URL can point to something like an Internet-Draft or a web page.

7.3. Media Type ("MIME Type")​

The Internet media type [RFC6838] for CBOR data is application/cbor.

Type name: application

Subtype name: cbor

Required parameters: n/a

Optional parameters: n/a

Encoding considerations: binary

Security considerations: See Section 8 of this document

Interoperability considerations: n/a

Published specification: This document

Applications that use this media type: None yet, but it is expected that this format will be deployed in protocols and applications.

Additional information: Magic number(s): n/a File extension(s): .cbor Macintosh file type code(s): n/a

Person & email address to contact for further information: Carsten Bormann [email protected]

Intended usage: COMMON

Restrictions on usage: none

Author: Carsten Bormann [email protected]

Change controller: The IESG [email protected]

7.4. CoAP Content-Format​

Media Type: application/cbor

Encoding: -

Id: 60

Reference: [RFC7049]

7.5. The +cbor Structured Syntax Suffix Registration​

Name: Concise Binary Object Representation (CBOR)

+suffix: +cbor

References: [RFC7049]

Encoding Considerations: CBOR is a binary format.

Interoperability Considerations: n/a

Fragment Identifier Considerations: The syntax and semantics of fragment identifiers specified for +cbor SHOULD be as specified for "application/cbor". (At publication of this document, there is no fragment identification syntax defined for "application/cbor".)

The syntax and semantics for fragment identifiers for a specific "xxx/yyy+cbor" SHOULD be processed as follows:

For cases defined in +cbor, where the fragment identifier resolves per the +cbor rules, then process as specified in +cbor.

For cases defined in +cbor, where the fragment identifier does not resolve per the +cbor rules, then process as specified in "xxx/yyy+cbor".

For cases not defined in +cbor, then process as specified in "xxx/yyy+cbor".

Security Considerations: See Section 8 of this document

Contact: Apps Area Working Group ([email protected]) Author/Change Controller: The Apps Area Working Group. The IESG has change control over this registration.