I wanted to clarify something in the IETF Origin draft[1], which is now going to serve as the basis for HTML5's Origin.
Section 5 requires that when a user agent provides the Origin header, it must either send "null" or the ASCII serialization of the origin. ASCII serialization (and Unicode serialization) stipulates that if an origin is not a scheme/host/port tuple, then it must return "null". Section 2 allows implementations to define other types of origins in addition to the scheme/host/port tuple. So my question is, if a user agent defines another type of origin, but is required to send "null" for it in the Origin header, is there some other use for defining other types of origins? - Bil [1] http://www.ietf.org/internet-drafts/draft-abarth-origin-00.txt