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Concise Binary Object Representation Maintenance and Extensions (cbor)

WG Name Concise Binary Object Representation Maintenance and Extensions
Acronym cbor
Area Applications and Real-Time Area (art)
State Active
Charter charter-ietf-cbor-03 Approved
Document dependencies
Additional resources CBOR playground
Collection of CBOR content
Document repositories
Zulip Stream
Personnel Chairs Barry Leiba, Christian Amsüss
Area Director Orie Steele
Mailing list Address
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Charter for Working Group

Concise Binary Object Representation (CBOR, RFC 7049) extends the
JavaScript Object Notation (JSON, RFC 8259) data interchange format to
include binary data and an extensibility model, using a binary
representation format that is easy to parse correctly. It has been
picked up by a number of IETF efforts (e.g., CORE, ANIMA GRASP) as a
message format.

The CBOR working group has updated RFC 7049 to deal with existing
errata, and the new version, draft-ietf-cbor-7049bis, is in the RFC
Editor queue to become an Internet Standard.

Similar to the way ABNF (RFC 5234/7405) can be used to describe the set
of valid messages in a text representation, it is useful for protocol
specifications to use a description format for the data in CBOR-encoded
messages. The Concise Data Definition Language (CDDL) is such a
description technique that has already been used in CORE, ANIMA, CDNI,
and efforts outside the IETF.

CDDL has been published as RFC 8610. While this specification has been
completed, several new features were raised during the update process
that were not included, in order not to delay publication, and to allow
publication in the Standards Track. One example of such a feature is the
ability to combine multiple CDDL files together using a mechanism other
than manually concatenating them together for processing. The working
group will collect these features as well as other features that are
raised by users of CDDL, evaluate their utility and, where warranted,
progress them either in a standalone document or as part of a new
edition of the specification.

The working group will define the approach to further evolving CDDL as a
sequence of editions, which might also add further extension points,
probably as part of the introduction of the next edition of the CDDL
base specification. The body of existing specifications that make use of
CDDL is considered precious, and the WG will set out not to damage their

The working group will evaluate the necessity of providing advice and
guidance for developers using CBOR and CDDL. It is currently expected
that this would be done using a Wiki of some type. This work would not
be expected to be published by the IETF as an RFC.

There are a number of additional CBOR tagged types and CBOR related
media type specifications that are currently adopted by the working
group, are work items in other working groups, or exist as individual
submissions. Additionally, there are expected to be other such documents
that will come to the attention of the working group. In some cases, the
working group expects to adopt and publish these proposals, and for
those the working group will evaluate them individually and decide about
adoption and milestones. Proposals that are deemed to be out of scope
for the working group, for example because they are too narrow in
purpose, may still be published as individual submissions or in another
groups if there is a specific need. The CBOR group will review these
proposals on request.