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Concise Binary Object Representation (CBOR) Tags for Time, Duration, and Period

Document Type Expired Internet-Draft (cbor WG)
Authors Carsten Bormann , Ben Gamari , Henk Birkholz
Last updated 2021-11-20 (Latest revision 2021-05-19)
Replaces draft-bormann-cbor-time-tag
Stream Internet Engineering Task Force (IETF)
Intended RFC status (None)
Expired & archived
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This Internet-Draft is no longer active. A copy of the expired Internet-Draft can be found at:


The Concise Binary Object Representation (CBOR, RFC 8949) is a data format whose design goals include the possibility of extremely small code size, fairly small message size, and extensibility without the need for version negotiation. In CBOR, one point of extensibility is the definition of CBOR tags. RFC 8949 defines two tags for time: CBOR tag 0 (RFC3339 time as a string) and tag 1 (Posix time as int or float). Since then, additional requirements have become known. The present document defines a CBOR tag for time that allows a more elaborate representation of time, as well as related CBOR tags for duration and time period. It is intended as the reference document for the IANA registration of the CBOR tags defined.


Carsten Bormann
Ben Gamari
Henk Birkholz

(Note: The e-mail addresses provided for the authors of this Internet-Draft may no longer be valid.)