- From: Dominik Tomaszuk <ddooss@wp.pl>
- Date: Mon, 01 Apr 2013 15:12:12 +0200
- To: Melvin Carvalho <melvincarvalho@gmail.com>
- CC: Henry Story <henry.story@bblfish.net>, Mo McRoberts <Mo.McRoberts@bbc.co.uk>, public-webid <public-webid@w3.org>
01.04.2013 14:57, Melvin Carvalho: > > > > On 1 April 2013 09:39, Henry Story <henry.story@bblfish.net > <mailto:henry.story@bblfish.net>> wrote: > > > On 1 Apr 2013, at 01:55, Mo McRoberts <Mo.McRoberts@bbc.co.uk > <mailto:Mo.McRoberts@bbc.co.uk>> wrote: > > > > > On Sun 2013-Mar-31, at 20:33, Henry Story > <henry.story@bblfish.net <mailto:henry.story@bblfish.net>> > > wrote: > > > >> No, it is a thing that does stuff. There is no problem with > calling your web server an agent. Browsers are called user agents, > presumably because there are server agents. There is a whole field > of programming called agent oriented programming. > > > >>> Similarly, I have applications which have their own client > certificates for communicating with servers: these are issued > specifically to the application so that it can authenticate > autonomously with an identity which is deliberately distinct from > any human involved in its development and operation. Again, > describing a webapp as a foaf:Agent strikes me as dubious stretching > of the term 'agent', there (compared to, say, an application which > is operating under the "direction" of an operator). > >> > >> No there is no problem with that. foaf:Agent is more general > that human agents, and so you can give a webid to a software > >> agent and relate it via the cert:key to a public key. No problem. > > > > If you ascribe foaf:Agent to everything which has some property > which means it may at some point fall within the definition given, > then you end up applying foaf:Agent to pretty much everything… > > You should discuss that with Dan Brickley on the foaf mailing list > if you think his definition is > so close to being a owl:Thing that it's not worth having the > distinction. > > We don't assign the domain of :key or the range of :identity to any > agent, but to those > for which the following is true: > > :identity a rdf:Property, owl:ObjectProperty; > vs:term_status "archaic"; > rdfs:label "identity"@en; > rdfs:isDefinedBy <cert#>; > skos:editorialNote """ > It turns out that this relation is unintuitive to write > out and to name. > One should instead use cert:key > """@en; > rdfs:comment """ > the identity of the public key. This is the entity that knows > the private key and > so can decrypt messages encrypted with the public key, or > encrypt messages that can > be decrypted with the public key. > """@en; > owl:inverseOf :key; > rdfs:domain :PublicKey . > > > That is it has to be something that can be responsible for a private > key - keeping > it safe from other agents within reason, and it has to be something > that can encrypt > and decrypt messages with the key. Those are very clearly agent like > things. > Software agents can be such things. > > > > > This is the distinction, I guess, between 'is defined as an > agent' and 'has the properties of an agent' — and I suppose why > X.509/LDAP has a distinction between 'structural' and 'auxiliary' > classes (the former being defining qualities, the latter describing > facets). > > > > What about, say, a piece of digital media? There are situations > where encoded media has its own keys conforming otherwise to the > ontology, and it's a bit of a stretch to say that *it* is an agent. > > Does digital media also have its private keys with which it can sign > something? Is Holloywood going to > encrypt digital media and add the private key to the media too, so > that the media can then do what? > Clearly not. So they don't conform to the ontology > > But perhaps this will become more obvious if you give us the use > case. My guess is that this > will reveal that you need a very different relation. And I am not > against that. > > > > > Flipping this around the other way, why _should_ the domain be > restricted to foaf:Agent? What practical problems does it cause? > (Noting that this isn't necessarily modifying the definition of a > WebID, just that anything can have a key or even a certificate > associated with it). > > Because we want a relation relating the Agent that is doing the > encryption decryption using the given key. > We have been using that since the beginning of WebID. > Other relations are possible, and it is easy to create new ones if > needed. > > > This is interesting logic so you want one relation that relates a key to > a URI and one that relates a key to an agent. Logically they should be > named something like "key" and "agentKey", right? The downside of this > suggestion is that implementations would need to change. > > Though I think we have consensus slightly in favour rdfs : Resource In which point rdf:Resource is better than owl:Thing? I do some ontology state-of-the-art and I don't see too much ontologies with uses rdfs:Resource in rdfs:domain or rdfs:range. My conclusion to these aproaches is that rdfs:Resource is used in low-level ontologies and cert ont isn't in that level. Probably better consensus is owl:Thing. Of course, I don't change my mind and I still think that foaf:Agent is better. D. > > > > > > > M. > > > > -- > > Mo McRoberts - Analyst - BBC Archive Development, > > Zone 1.08, BBC Scotland, 40 Pacific Quay, Glasgow G51 1DA, > > MC3 D4, Media Centre, 201 Wood Lane, London W12 7TQ, > > 0141 422 6036 (Internal: 01-26036) - PGP key CEBCF03E > > > > > > > > ----------------------------- > > http://www.bbc.co.uk > > This e-mail (and any attachments) is confidential and > > may contain personal views which are not the views of the BBC > unless specifically stated. > > If you have received it in > > error, please delete it from your system. > > Do not use, copy or disclose the > > information in any way nor act in reliance on it and notify the > sender > > immediately. > > Please note that the BBC monitors e-mails > > sent or received. > > Further communication will signify your consent to > > this. > > ----------------------------- > > Social Web Architect > http://bblfish.net/ > > -- Dominik Tomaszuk Research Fellow University of Bialystok Poland
Received on Monday, 1 April 2013 13:12:39 UTC