I'm reading draft-nottingham-http-link-header-06 and I have a few comments, or at least things I am confused about. Section 4 says: "As such, relation types are not format-specific, and MUST NOT specify a particular format or media type that they are to be used with." Does this refer to the format or media type of the context or the target? I think there are reasonable use cases for a relation type to specify what the target format is supposed to be. For example, an application-specific extension relation type to link http://example.com to an API endpoint (whatever that means) could say the target must be (or should be) application/x-example-format+xml. Or a relation type could say the target must be a subtype of the image/ mime type. In the ABNF in section 5, enc2231-string refers to extended-value in section 7 of RFC2231. However, "extended-value" isn't explicitly defined anywhere in RFC. The strange thing is that it's *used* in other ABNF constructions of RFC2231, like extended-parameter; but I don't see it in the left hand side of any ":=" Below the ABNF in section 5, it says: "If the URI-Reference is relative, it MUST be resolved as per [RFC3986], Section 5." Does this mean that if a client parsing a Link header finds a relative URI reference, it MUST resolve it to an absolute URI; or does it mean a server MUST resolve relative URIs to absolute URIs before sending the Link header to a client? I think it should be clarified what side (client or server) that MUST applies to. Same for "If the anchor parameter's value is a relative URI[...]" in the paragraph that follows. Editorial issue: the last line of page 5 (second paragraph after ABNF in section 5) should be moved to the beginning of page 6 for better readability. (this is known as an "orphan line") Apologies in advance if any of these issues were raised already (I'm not on the mailing list myself), or if I'm posting to the wrong list for this topic. Since I'm not subscribed to the list (and I'm having technical problems to access gmane.org), I'd appreciate if you Cc: me in any replies. -- Nicolas _______________________________________________ Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf