- From: Melvin Carvalho <melvincarvalho@gmail.com>
- Date: Mon, 1 Apr 2013 15:17:12 +0200
- To: Dominik Tomaszuk <ddooss@wp.pl>
- Cc: Henry Story <henry.story@bblfish.net>, Mo McRoberts <Mo.McRoberts@bbc.co.uk>, public-webid <public-webid@w3.org>
- Message-ID: <CAKaEYh+40-qUJhL9kBvFM9N5CbDbb2eYAtMN+K4Y6SoM1zGPmA@mail.gmail.com>
On 1 April 2013 15:12, Dominik Tomaszuk <ddooss@wp.pl> wrote: > 01.04.2013 14:57, Melvin Carvalho: > >> >> >> >> On 1 April 2013 09:39, Henry Story <henry.story@bblfish.net >> <mailto:henry.story@bblfish.**net <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<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. > Good point, actually foaf uses owl : Thing > > 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 13:17:42 UTC