Re: Proposed draft RDF Graph vocabulary

On Mar 24, 2004, at 15:46, Patrick Stickler wrote:
>>
>> It appears to me that we are having three classes:
>>
>> 1. Graphs
>> 2. Web performatives
>> 3. Agents

We also have Warrants, which relate an authority with
a signature, and possibly other authentication-relevant
information.

So we're actually relating graphs with warrants directly,
and graphs with authorities indirectly, via the authenticated
warrants.

Patrick


>>
>> that are getting related.
>>
>> There are two variations of graph:
>> 1.1 an abstract graph like the sentence "The water is green."
>> 1.2.an concrete graph / graph instance, that *is named* and can be
>> published. There is a 1-to-many relationship between the abstract 
>> graph "The
>> water is green." and it's named instances. So I would prefer to speak 
>> about
>> *graph instances* in the context of named graphs and web publishing.
>>
>> Web performatives connect *named graph instances* with named agents.
>>
>> There is also a 1-to-many relationship between a graph instance and 
>> the
>> agents connected to it via the performative. Thus I'm still not 
>> convinced
>> that we have to pick one of these agents and declare him as the owner 
>> of the
>> instance.
>
> There can be more than one first-party agents associated. The
> distinction is really between first-party (named in the graph
> itself) and third-party (named in some other graph). E.g. given
>
> :G ( :G swp:assertedBy ex:Bob . :G swp:assertedBy ex:John . ...)
> :H ( :H swp:assertedBy ex:Mary . :G swp:assertedBy ex:Mary . ...)
>
> then Bob and John have a first-party relationship to G
> but Mary has a third-party relationship to G, yet all three
> assert graph G.
>
> We can treat the first-party agents as the owners/publishers of the
> graph, and the third-party agents as supporters/affirmers of the graph.
>
>> What do we gain in a scenario where the "owner" is the agent who
>> did the original naming of the graph (that is how I understand your 
>> concept
>> of owner) and 20 other agents also perform performatives on this 
>> named graph
>> instance? I think nothing.
>
> There's a significant benefit to the distinction. Those authorities 
> named
> in the graph itself, such that the signature(s) validate have a tighter
> relationship to the graph, and hence a stronger claim of 
> ownership/authorship.
>
> I.e. the owner of the graph is the first-party authority identified in
> the graph. Others may assert/affirm that graph, but they are not the
> publishers of it -- if they were, they *they* would be named explicitly
> in the graph and not someone else.
>
> Basing ownership on who named a graph I think would be difficult to
> do in practice. Tell me quick, in ten seconds, who minted the following
> URI:  http://sjaiu.bib.to/qijeoaafoail/72812784/gkai.ais ???
>
> Better to have the authority explicitly named in the signed graph, and
> treat the first-party authority as the owner/publisher.
>
>>
>> Using signatures also don't make signing agents special (=owners), 
>> because
>> several agent can sign the same named graph instance.
>
> True, and then they are joint owners/publishers, if that signing occurs
> in the graph itself.
>
>>
>> So wouldn't it be an idea to forget about ownership and authority and 
>> just
>> use the term *information provider* for agents instead. In our 
>> scenario we
>> are  having two basic roles an agent can embody: Information provider 
>> and
>> information consumers. Thus concerning publishing information 
>> provider would
>> be more precise than just calling the think "agent".
>
> No, I think we need to be clear about first-party vs. third-party
> authority. Otherwise, you're left hanging in the wind when it comes
> to resolving mutual conflicting claims of ownership all made within
> graphs other than the graph in question. Having the authority 
> explicitly
> stated in the signed/authenticated/validate graph makes it crystal
> clear who the owner/publisher really is, since no'one else would be
> able to produce such a graph and have the signatures check out.
>
> Patrick
>
> --
>
> Patrick Stickler
> Nokia, Finland
> patrick.stickler@nokia.com
>
>

--

Patrick Stickler
Nokia, Finland
patrick.stickler@nokia.com

Received on Thursday, 25 March 2004 02:48:30 UTC