Composite CapabilityPreference Profiles
Composite Capability/Preference ProfilesCC/PP is an RDF-based framework for describing and managing software and hardware profiles. It is a way to specify what an entity (or a user agent, such as a device, a browser, or a generalized client) is capable of doing, and what its preferences are within that set of capabilities. The framework can be used in a static and dynamic context. In the static context, preset profiles are used to select the appropriate content to send to a requester. In the dynamic case, where content is being generated on the fly, the profiles are used to transform typical XML content into the appropriate representation based on the requester's preferences. This flexibility allows for negotiations between clients and servers or between peer nodes. In the case of Web browsers or PDAs, for example, where displaying information is of major consideration, CC/PP enables the production of optimized markup for display. One of the advantages of CC/PP is that the framework can be used to generate and provide generic profiles that are accessible on the Web. For example, hardware or software vendors can provide profiles for their various products, eliminating the need for an individual client (whether a device or an application) to transmit their own profile with every transaction. This is an important consideration for devices with limited bandwidth. An excerpt of such a generic profile, in this case for an Ericsson phone, is shown in Listing 23.2. Aside from the significant fact that the profile is represented in RDF, a quick scan through the various components of the document reveals a complete set of definitions for the hardware platform, the software platform, and the network characteristics of the phone. As this is a profile for a mobile phone with well-known, nonchangeable capabilities, it can be found online, in this case at http://mobileinternet.ericsson.com/UAprof/T68R1.xml. Listing 23.2 Excerpt of CC/PP Profile for an Ericsson T68R1 Mobile Phone<?xml version="1.0"?> <RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:prf="http://www.wapforum.org/UAPROF/ccppschema-20000405#"> <rdf:Description > <prf:component> <rdf:Description > <prf:ScreenSize>101x80</prf:ScreenSize> <prf:Model>T68R1</prf:Model> <prf:InputCharSet> <rdf:Bag> <rdf:li>ISO-8859-1</rdf:li> <rdf:li>US-ASCII</rdf:li> <rdf:li>UTF-8</rdf:li> </rdf:Bag> </prf:InputCharSet> <prf:ScreenSizeChar>15x6</prf:ScreenSizeChar> <prf:BitsPerPixel>8</prf:BitsPerPixel> <prf:ColorCapable>Yes</prf:ColorCapable> <prf:TextInputCapable>Yes</prf:TextInputCapable> <prf:ImageCapable>Yes</prf:ImageCapable> <prf:Keyboard>PhoneKeypad</prf:Keyboard> <prf:NumberOfSoftKeys>0</prf:NumberOfSoftKeys> <prf:Vendor>Ericsson Mobile Communications AB</prf:Vendor> <prf:OutputCharSet> <rdf:Bag> <rdf:li>ISO-8859-1</rdf:li> <rdf:li>US-ASCII</rdf:li> <rdf:li>UTF-8</rdf:li> <rdf:li>ISO-10646-UCS-2</rdf:li> </rdf:Bag> </prf:OutputCharSet> <prf:SoundOutputCapable>Yes</prf:SoundOutputCapable> <prf:StandardFontProportional>Yes</prf:StandardFontProportional> <prf:PixelsAspectRatio>1x1</prf:PixelsAspectRatio> </rdf:Description> </prf:component> <prf:component> <rdf:Description > <prf:AcceptDownloadableSoftware>No</prf:AcceptDownloadableSoftware> </rdf:Description> </prf:component> <prf:component> <rdf:Description > <prf:SecuritySupport>WTLS class 1/2/3/signText</prf:SecuritySupport> <prf:SupportedBearers> <rdf:Bag> <rdf:li>TwoWaySMS</rdf:li> <rdf:li>CSD</rdf:li> <rdf:li>GPRS</rdf:li> </rdf:Bag> </prf:SupportedBearers> </rdf:Description> </prf:component> </rdf:Description> </RDF> It is clear that P2P technologies could greatly benefit from such a framework in order to describe the capabilities and preferences of heterogeneous distributed nodes in a P2P environment. |
