Re: urn-5 vs hashes (was: Re: [Gzz] RE: [ba-ohs-talk] Fenfire, RDF (re "Towards a Standard Graph-Based..."))

[Tuomas Lukka]

On Mon, Mar 10, 2003 at 01:52:51AM -0800, Kevin Keck wrote:
> on 2003/03/08 11:20 AM, Benja Fallenstein at address@hidden wrote:
> > (replied to Danny by private mail)
> > 
> >> afaik the cryptographic content hash forms the URI (urn-5)
> > 
> > Nope, urn:urn-5 is for random numbers (when you create a new node and
> > want to assign a random URI to it) and is not related to hashes. There's
> > no URI scheme or URN namespace for hashed data, yet (AFAIK).
> > 
> > (Sorry to send this thru the lists, but it would be bad if this
> > misconception stood without refutation...)
> 
> Actually, there's at least three used with the various file sharing apps:
> 
> MAGNET, apparently supported by some Gnutella programs. Uses sha1. Example:
> <magnet:?xt=urn:sha1:ZETNTXVNDO2DS32627BQNKIADS3RT3T5&dn=Shareaza1700.exe>
> 
> eDonkey ed2k URIs, which use MD4. Example:
> <ed2k://|file|Shareaza1700.exe|1330539|b29e2440d84ed468a63971220667786f|/>
> 
> sig2dat URIs, used with Kazaa, Grokster, etc. Not sure what hash. Example:
> <sig2dat://|File:%20Shareaza1700.exe|Length:%201330539%20Bytes,%201299KB|UUH
> ash/kHiGJMFBOMT2rdMU=|>

Yes, we are aware of at least of the two first ones, but the problem is that
they're not *real* URIs (i.e. officially defined to be part of the URI 
namespace).

        Tuomas