Re: Seiwald Q & A -- "GET for EDIT" cookies

Robert S. Thau (
Tue, 3 Sep 1996 19:53:36 -0400

      If I read the spec right, Content-Version reflects the contents
      of the document.  That is, if the same document is dished up
      twice it is supposed to have the same Content-Version value.

This may be a silly question, but it's probably not the last time
you'll hear it, so I might as well ask --- how does this differ from
an HTTP/1.1 entity tag (as used in the Etag:, If-match:, If-none-match:,
and If-range: headers)?

(These are opaque tags which are intended to identify different
variants of a resource for caching purposes.  They come in two
varieties, "strong" and "weak".  A strong entity tag always denotes
the exact same set of octets.  A weak one may denote multiple versions
--- in the colloquial sense --- with minor, semantically insignificant
differences, which may still differ enough so, for instance, you can't
mix byte-ranges of different ones willy-nilly).