- From: boyera stephane <boyera@w3.org>
- Date: Mon, 7 Apr 2003 10:35:54 +0200
- To: <www-mobile@w3.org>
-- Stephane Boyera stephane@w3.org W3C +33 (0) 4 92 38 78 34 BP 93 fax: +33 (0) 4 92 38 78 22 F-06902 Sophia Antipolis Cedex, France -----Original Message----- From: Claudia Alvarez Rolins [mailto:claudia@telemidia.puc-rio.br] Sent: Friday, April 04, 2003 9:12 PM To: Luu Tran Cc: Butler, Mark; www-mobile@w3.org Subject: [Moderator Action] Re: FW: CC/PP Structure and Vocabularies last call working draft - acouple of questions/issues from Claudia Hi Luu, many thanks for your reply and for the additional information that you have provided me. As I said to Mark, I would like very much to join and help the group but unfortunately, I have a couple of months to complete my master thesis which is now my highest priority. Anyway, I will follow the group work on CC/PP and maybe in the future, be in a situation where I can offer myself to make contributions to the group. Best Regards, CR ----- Original Message ----- From: "Luu Tran" <Luu.Tran@Sun.COM> To: <claudia@telemidia.puc-rio.br> Cc: "Butler, Mark" <Mark_Butler@hplb.hpl.hp.com>; <www-mobile@w3.org> Sent: Friday, April 04, 2003 3:30 PM Subject: Re: FW: CC/PP Structure and Vocabularies last call working draft - acouple of questions/issues from Claudia > Hi Mark, Claudia, > > Thanks much for your comments. Please see my responses below. > > Thanks, > Luu > > Butler, Mark wrote: > > FYI - anybody else got any views on the issues Claudia raises? > > > > -----Original Message----- > > From: Butler, Mark > > Sent: 04 April 2003 11:08 > > To: 'claudia@telemidia.puc-rio.br'; 'luu.tran@sun.com' > > Subject: FW: CC/PP Structure and Vocabularies last call working > > draft - a couple of questions/issues from Claudia > > > > > > Hi Claudia > > > > See my responses to your questions and issues below > > > > -----Original Message----- > > From: Claudia Alvarez Rolins [mailto:claudia@telemidia.puc-rio.br] > > Sent: 04 April 2003 00:30 > > To: Butler, Mark > > Subject: Fw: CC/PP Structure and Vocabularies last call working > > draft - a couple of questions/issues from Claudia > > > > > >>Questions and Issues > > > > > >>1) What is the difference between content adaptation and > > > > contextualization? > > > > Content adaptation is the process of adapting content (say in XML) > > to various target devices (e.g. HTML, WML, XHTML). As for contextualization, > > I'm afraid I don't know what that means - but the W3C DI-WG has been working > > on a glossary which presumably defines it - Luu? Is the term > > contextualization used in the CC/PP WD? If so is it not defined in > > the glossary at the end? > > Contextualization is used once in the introduction, but not defined in > the glossary. I'm not sure what it means either, but by the way it's > used, I'd guess that contextualization is the process of setting > context, i.e. context is the output. This is different from content > adaptation which is one way of reacting to context, i.e. context is > the input. I agree that we either need to remove this term, or define > it in the glossary. > > >>2) Proxy behavior was removed from CC/PP Structure and Vocabularies > >>and nowdays this specification indicates the use of CC/PP as a > >>profile data format to guide/orient a server on determining the most > >>appropriate form of a resource to deliver to a client. However > >>content adaptation can also be performed at the client side during > >>the content presentation (also known as dynamic adaptation). > > > > > > Yes you can do content adaptation at the client side, but at the > > moment the > > technology I would recommend there is Cascading Stylesheets Media Queries - > > see the W3C CSS work for more details. Whereas CC/PP only defines a > > data format, CSS MQ also defines a query format. Therefore it is > > easier to use. > > Of course, CSS MQ defines its own vocabulary. There was some disagreement in > > the W3C about whether CSS MQ should exist, or whether it should use CC/PP. > > However as I've described in many of my reports I think CC/PP is > > much more > > complicated to deploy than it needs to be, and this is due in part > > from unnecessary complexity it inherits from RDF/XML. CSS MQ is a > > much more pragmatic approach to the problem. I see the DI-WG core > > device characteristics work as addressing the need for a common > > vocabulary here. > > > > > >>Is CC/PP not indicated to describe context information (e.g.: the > >>origin server capabilities) that would be helpful to support the > >>content > > > > adaptation > > > >>process at the client side? > > > > > > You could use CC/PP in this way and then use a process a bit more > > like transparent content negotiation in HTTP. One of my earlier > > papers describes > > a content negotiation approach with CC/PP. However it is actually > > quite difficult to do things like this in CC/PP, because if you > > strictly follow > > the CC/PP WD, CC/PP can't express disjunctions or preference > > ordering. > > > > > >>Is CC/PP only useful to describe client capabilities? > > > > > > For the moment, that is how most people are using it, so that is > > what is reflected in the current WD. In the future this may change > > though. The CC/PP > > work needs more support so if you are interested in this perhaps you would > > consider joining and helping? > > > > > >>3) If a proxy behavior was removed from CC/PP Structure and > > > > Vocabularies, > > > >>is it correct to maintain the sentence "It is structured to allow a client > > > > > >>and/or a proxy to describe their capabilities by reference to a > >>standard profile...." at the fourth paragraph of the Introduction > >>section? > > > > > > No, this sentence probably needs rewording so I suggest you raise it > > formally with the DI-WG as they describe. > > Thanks for catching that. I'll remove it for the next revision. > > >>4) Why the issues on profile resolution mechanism not addressed is > >>the Working Draft from 25 March 2003? Will resolution rules adopted > >>by UAPROF > >>(override, locked, append) and data types be treated within the > > > > rdfs:comment > > > >>property? > > > > > > because unlike UAProf, CC/PP does not have any standardised > > processing or > > resolution policy. I think this is a mistake - without a > > standardised processing model, different processors might do very > > different things. I have raised this issue with the CC/PP WG, but it > > has been very hard to introduce changes to the CC/PP WD for two > > reasons > > - lack of group members and interest in the group > > - restrictions due to the current WG charter > > therefore it was decided not to address this in the current version. > > I'd also add that the DI-WG is chartered to produce a CC/PP protocol > document, in which we can address processing/resolution. > > > I'm sure the issue list would be interesting reading for you, but at > > the moment it isn't public. Try writing to Luu or the DI-WG and ask > > if you can > > see a copy, because the DI-WG has a public policy so it would be interesting > > to see if this extends to the CC/PP Work. > > A public version of the issues list is at: > > http://www.w3.org/2003/03/ccpp-cr-issues-20030320.html > > > In JSR-188, we solve this problem by just adopting the UAProf > > resolution model. In a way, JSR-188 is really just focusing on > > UAProf as that is the > > only CC/PP application that is defined in enough detail to be implemented. > > > > > >>5) Is there any test or example that shows how CC/PP can be used to > >>describe users personal preference? Or CC/PP not applied to describe > >>this type of context information? > > > > > > this is a difficult one. There are a couple of viewpoints i.e. > > > > i) if we express personal preferences, then there are privacy issues > > so we > > have to adopt a privacy framework like P3P > > > > ii) does P3P really work? It is just a way of a site claiming it has > > a certain privacy policy - what if it lies? Therefore surely if > > there is privacy concerns about a piece of information surely we > > should not send it? > > Privacy is a complicated issue. For example people have suggested > > that if a > > PC says it only audio capable, then it indicates a blind user, so > > there is > > the possibility of discrimination, so we should use a privacy > > system. However how do we avoid this - if we send no information, we > > are in the same > > situation as if we don't use CC/PP? Personally I don't understand > > how you > > can use specs to stop discrimination, because you don't know how > > people are > > going to discriminate. For example I might decide to discriminate against > > Nigerians, because that's where all the spam comes from, and I might > > do that > > by maintaining a list of Nigerian IP subnets - how do you stop me > > doing that > > (this is a theoretical example of course)? > > > > iii) it sounds like to send personal preferences, we need something > > more complicated than CC/PP. However we need CC/PP to solve some > > real issues today e.g. whether a device supports frames, whether it > > is mime/multipart > > capable etc. So why not just use CC/PP for describing client capabilities > > for now? > > > > iv) The other adaptation information that servers need is language > > preferences? Is this personal information? > > I agree with Mark. I'd just add that the CC/PP default override > mechanism can be used to indicate a limited level of personal > capability preferences. For example, even if my device can display > color images, I may choose to configure it to only request black and > white images to reduce network bandwidth consumption. As Mark > describes, conveying personal preferences unrelated to device > capabilities is difficult and (in my view) inappropriate as part of > CC/PP profiles. There is another more widely accepted industry effort > underway to address this problem: > > http://www.projectliberty.org/ > > >>6) Why does Tayeb Lemlouma propose the Universal Profiling in a > >>different direction than UAPROF? Could the efforts be joined? > > > > > > The best person to ask here would be Tayeb. I could tell you my > > opinion, but > > it would just be my opinion and Tayeb might disagree. However I > > think you > > are highlighting that there is a need for a standard vocabulary > > here, not > > lots of separate ones like UAProf, Universal Profiling etc and that > > need should be addressed by the DI-WG in the core device > > characteristics work. > > > > > >>7) While reading the CC/PP Structure and Vocabulary I always have > >>the feeling that CC/PP only supports the three > >>components: hardware, software and browser. Shouldn´t this > >>specification be more explicit and describe that other components > >>could be created such as UAPROF did? > > > > > > No, because the spec just defines a structure, not a vocabulary. The > > components it gives are examples, so you don't have to use them, you > > can create others. Despite the specs length, it doesn't really say > > that much. > > > > Personally I don't think that components actually serve any purpose > > in CC/PP, and they actually make processing more difficult so I > > think they should be removed. If we were starting CC/PP again, then > > the way I would do > > it would be to start with a number of focused use cases, then use > > these use > > cases to check that there was sufficient complexity in the spec to > > meet the > > use cases but no more. At present, there is quite a bit of > > unnecessary complexity in the spec, but sadly it is not possible to > > address this in the > > current version. The hope is to get the current version out the > > door, then > > if there is sufficient interest, may be there will be a version 2. > > > > thanks, best regards > > > > Dr Mark H. Butler > > Research Scientist HP Labs Bristol > > mark-h_butler@hp.com > > Internet: http://www-uk.hpl.hp.com/people/marbut/ > > > > > > >
Received on Monday, 7 April 2003 04:35:55 UTC