impl-info: A link relation type for disclosing implementation information

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Document Type Expired Internet-Draft (individual)
Author Carsten Bormann 
Last updated 2018-08-01 (latest revision 2018-01-28)
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When debugging an interoperability problem, it is often helpful to have information about the implementation version of a peer. To enable the disclosure of such information, HTTP defines header fields such as Server and User-Agent. In CoAP, it is rarely appropriate to send information of this kind in every request or response. Instead, the present specification defines a link relation type, impl-info, that can be used to convey this information via the self-description capabilities of the /.well- known/core resource and the CoRE resource directory.


Carsten Bormann (

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