Re: URIs vs. URNs vs. URLs

> Ummm, where do you get that "evident" from?  In my experience, a typical
> bookmarked URL will outlast a URN.  The reason is because unimplemented
> persistent naming mechanisms go in and out of fashion.  A name (ANY NAME)
> will never be persistent until someone makes enough good use of that name
> to justify the cost of making it persist.  Persistence is not, and never
has
> been, a function of the syntax used to create the name.

Hello everybody.
My two cents:

There are different types of URI.
They are all identifiers.
Some are "more persistent" than others.

Example
URN:ISBN:1-56592-528-9
is definitively persistent:  (an O'Reilly book: "Apache, The Definitive
Guide")

Some others are less good as persistency,
but maybe better for other aspects.
The URL is an identifier and a locator (and maps to IP using DNS),
that makes them not so good in persistency, but
very good for resource retrieving on the network.

I think the questions are:
"Is there a better URI we can use to retrieve resources on the network?"
"Is it enough using URLs as they are, but with a careful use of them ?"


Best Regards,
Giosue' Vitaglione