Re: [decade] FW: Last Call: <draft-farrell-decade-ni-07.txt> (Naming Things with Hashes) to Proposed Standard

Sam Hartman <hartmans-ietf@mit.edu> Sat, 09 June 2012 00:43 UTC

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From: Sam Hartman <hartmans-ietf@mit.edu>
To: Stephen Farrell <stephen.farrell@cs.tcd.ie>
Subject: Re: [decade] FW: Last Call: <draft-farrell-decade-ni-07.txt> (Naming Things with Hashes) to Proposed Standard
References: <E33E01DFD5BEA24B9F3F18671078951F23A88B0C@szxeml534-mbx.china.huawei.com> <CAGnGFMKjv2QR+ebynnC2GktpYf2QEx73n+0_ZZeyJrAmTYDnjg@mail.gmail.com> <CABkgnnVga6Dn5cVQA+AFzd=4LN9Y65YcJEwUiiwVJeSqg=mS0Q@mail.gmail.com> <4FD29389.5060900@cs.tcd.ie>
Date: Fri, 08 Jun 2012 20:43:48 -0400
In-Reply-To: <4FD29389.5060900@cs.tcd.ie> (Stephen Farrell's message of "Sat, 09 Jun 2012 01:06:33 +0100")
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Cc: Jonathan A Rees <rees@mumble.net>, ietf@ietf.org
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Add me as a +1 for the idea that content-type is important for this.
I tend to agree with the arguments given so far. Namely, for some
important use cases you're going to want to know the content type and
guessing is  really a bad idea.

That said, there are security considerations associated with specifying
a content type too.  I'm particularly imagining a situation where some
sort of deep inspection security appliance uses a different procedure
for deciding what kind of foo it is than the ultimate application. One
guesses based on byte stream another looks at a content type.  This is
well known; it's not new; it's probably even so documented that any
reasonably current set of MIME security considerations already includes
a reference.


I agree that your draft does not use the authority portion of a URI
consistent with section 3.2 of RFC 3986. The authority separates the
namespace exactly the way it doesn't in your scheme. It's a naming
hierarchy.  My main concern is whether the relative reference algorithm
described in section 5/4.2 of RFC 3986. In particular take a look at the
last part of section 1.2 of RFC 3986 regarding the disallowing of
/. Consider how you want relative references in an HTML document
resolved through a ni: URI to work.  I don't think your use of authority
provides good results. However I'm not sure that better results would be
achieved without hierarchy.  I hope though that these comments will help
inject some ways of reasoning about authority that are less mystical and
that lead to more practical discussion.