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