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Re: info scheme has no authority component, why?

From: Adam M. Costello BOGUS address, see signature <BOGUS@BOGUS.nicemice.net>
Date: Sat, 13 Mar 2004 05:29:10 +0000
To: uri@w3.org
Message-ID: <20040313052910.GB23689~@nicemice.net>

"Roy T. Fielding" <fielding@gbiv.com> wrote:

> Moving reg-name under host has the appropriate impact of reserving the
> ":" and "@" characters for a specific purpose, but no effect on any
> URI that might have been defined to use the old reg_name (which also
> reserved those characters).

RFC-2396 explicitly allows unescaped colons and at-signs in reg_name,
while 2396bis clearly disallows them in reg-name.  Consider
foo://a@b+c:4/.  According to RFC-2396, there is only one way to
decompose it:

reg_name=a@b+c:4
there is no port
there is no userinfo

According to 2396bis, there is only one way to decompose it:

reg-name=b+c
port=4
userinfo=a

Your claim of "no effect" requires me to ask:  Was this new
interpretation of existing URIs a goal of the grammar change, or an
unanticipated side-effect of it?

> Yes, it would be better to use either the generic authority syntax
> or the URN authority syntax for new URI schemes that make use of
> delegated naming authorities.

Thanks, that helps.  In the current 2396bis draft, it's not clear (to
me) that the "host" component, despite it's name, might not refer to
a host at all.  The natural assumption is of course that a component
named "host" refers to a host.  The last three paragraphs of section
3.2.2 reinforce that assumption: even as they warn that a reg-name is
not necessarily a hostname, they focus on network issues that apply only
to hosts, not to registry-based naming authorities like LCCN.

The very first sentence of that section is probably left over from an
earlier draft:

    The host sub-component of authority is identified by an IP
    literal encapsulated within square brackets, an IPv4 address in
    dotted-decimal form, or a host name.

Maybe something like this would clarify your intended semantics:

    The host sub-component of authority is either an IP literal
    encapsulated within square brackets, an IPv4 address in
    dotted-decimal form, or a registered name.  If it's a name, it can
    refer to a network host or some other kind of naming authority (the
    sub-component is called host for historical reasons).

AMC
http://www.nicemice.net/amc/
Received on Saturday, 13 March 2004 00:29:14 GMT

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