Re: URN namespaces for use in 'magnet' URIs

[Mykyta Yevstifeyev <[e-mail]>]

25.07.2011 15:51, Peter Saint-Andre wrote:
> On 7/24/11 11:05 PM, Mykyta Yevstifeyev wrote:
>> 24.07.2011 18:43, Peter Saint-Andre wrote:
>>> On 7/22/11 5:46 AM, Mykyta Yevstifeyev wrote:
>>>> Hello all,
>>>>
>>>> The 'magnet' URIs, which are quite popular with P2P networks, have an
>>>> element named "exact topic" which contains the URN, forming an URI like:
>>>>
>>>>> magnet:?xt=<URN>&<other parameters>
>>>> The URNs used in 'magnet' URIs must be a "hash URN", none of which are
>>>> currently officially registered.  The hash URN is smth. like
>>>> <urn:sha1:c3499c2729730a7f807efb8676a92dcb6f8a3f8f>   using SHA-1; see
>>>> Wikipedia page on 'magnet' URIs -
>>>> http://en.wikipedia.org/wiki/Magnet_URI_scheme#URN.2C_containing_hash_.28xt.29
>>>>
>>>> - for more examples of hash URNs.
>>>>
>>>> As I've mentioned, none of used hash URNs use the registered
>>>> namespaces.  Correspondingly, my question - is there a sense in
>>>> documenting such ones?
>>> Why not use UUIDs?
>>>
>>> http://tools.ietf.org/html/rfc4122
>> P2P networks use DHT, Distributed Hash Table, which identifies the file
>> using hashes.  See http://en.wikipedia.org/wiki/Distributed_hash_table
> I've heard of several people who are interested in defining a URN
> namespace for hashes. Such a namespace would be similar to the UUID
> namespace. However, RFC 4122 is not really a formal namespace in the
> sense of all other URN namespaces. URNs are supposed to be formally
> issued or generated by an authoritative entity that has responsibility
> over the namespace.
>
> RFC 3406 says:
>
>     Assumption #2:
>
>        The space of URN namespaces is managed.
>
> The UUID namespace is not managed. A hash namespace would not be
> managed. Although there is value in having a URI that enables people to
> use UUIDs or hashes, I don't think they should be URNs. (Yes, the UUID
> namespace already exists, but I don't think RFC 4122 would be published
> now if we were considering it again.)
Yes, as UUIDs, as hash URIs may not be managed; however, my point is 
that the latter are currently widely used.  I was asking whether they 
are OK to be documented; considering they may not suit the requirements 
for URNs documenting them won't be fine as well.  So the optimal 
approach is to let hash URNs be used further but retain them undocumented.

Mykyta
>
> Peter
>