> I think we don't particularly care whether a URN points to a changing
> resource or a static resource. What we care about is that a person
> has some means to find out what a symbol is for. The question
> is far bigger than static/dyanmic, draft/non-draft, all you want to do
> is know what you got.
Maybe I miss-parsed your sentence, but I think that the systems that
we build for caching, replication, distribution, location of URLs from
URNs will care quite a bit whether the URN is a changing resource or a
static one.
> Second, there has been some talk about delegation of registration
> authority. How are you going to get the registrar for a particular
> area to conform. If McGraw-Hill decides to use their pool of URN's
> in a contrary way do you think you have the clout to say I'm sorry
> you can't publish.
URNs are not like ISBN numbers, in that we're talking about using them
in systems and protocols; if someone builds a FTP server that doesn't
really talk the FTP protocol, then people won't be able to use it
effectively. If McGraw-Hill were to proclaim that some of their
variable URNs were static, people who maintained caches of McGraw-Hill
documents would get false cache hits. The system wouldn't work.
Secondly, we *could* very well use some scheme for URNs that couldn't
be subverted, e.g., use a one-way hash of the original document data
as the immutable URN, or use a URL with a time-stamp, rather than some
more subjective measure of 'identity' for the implementation.