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Liaison statement
Concerns from the W3C Technical Architecture Group regarding JSON

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State Posted
Submitted Date 2013-11-27
From Group W3C
From Contact Mark Nottingham
To Group json
To Contacts Matthew Miller <>
Paul Hoffman <>
Purpose For information
Attachments (None)
Dear All,

The W3C Technical Architecture Group has a concern regarding the ongoing
coordination of the industry standardization work on JSON.  JSON is a
key integration technology for Web applications and a key data
interchange format for the Web.  The current state of affairs, where
there are now two different JSON specifications which may be normatively
referenced, one developed in ECMA as ECMA-404 and one developed in IETF
as RFC 4627 and in last call as RFC 4627bis is not ideal and could lead
to confusion in the industry.  Because the two specs vary slightly, we
believe this could lead to interoperability issues.

For example, today there are JSON parsers (conforming to ECMA-404) that
can parse "42" (a JSON document consisting of a single integer). There
are also parsers (conforming to RFC 4627/draft-ietf-json-rfc4627bis-07)
that cannot parse "42" today, but they can be meaningfully upgraded to
do so too. This would not break applications using those parsers, unless
they depend on parsing "42" as an error, which is a far more unlikely
scenario than parsing it as 42 given precedence.

Regardless of the historical reasons for the current situation, the W3C
TAG believes that having one definition of JSON would be beneficial for
the Web and for the wider community of JSON implementors and JSON
consuming and producing applications.  We suggest that the IETF JSON
working group should re-enter discussions with ECMA TC39 in order to
facilitate aligning RFC 4627bis with the current ECMA-404 specification.

Thank you,

Philippe Le Hegaret,
IETF co-team contact for the W3C