HTTP "related protocols?"

  Hi,

  In the note in <http://www.w3.org/TR/xproc/#cv.request> in the
current CR from late November, one can read:

    In the case of simple "GET" requests, implementors are encouraged
    to support as many protocols as practical. In particular, pipeline
    authors may attempt to use p:http-request to load documents with
    computed URIs using the file: scheme.

  It sounds quite weird to me.  What does GET mean for another
protocol than HTTP?  In the same way, the first sentence in §7.1.10,
p:http-request says "The p:http-request step provides for interaction
with resources over HTTP or related protocols."  What is a "related
protocol?"  I can understand HTTPS, but which other one?

  Regards,

-- 
Florent Georges
http://www.fgeorges.org/