1 A Context Framework for Ambient IntelligenceA. Dogac, G. B. Laleci, Y. Kabak Middle East Technical University aVsonline.blogspot.com aVs 997 techfamily
2 Motivation AmI Web Services interoperable User ContextContext servers interoperable User Context Machine processable Security & privacy Web Services
3 Ambient Intelligence Ubiquitous computing Ubiquitous communicationIntelligent User Friendly Interfaces Better integration of technology into our environment, so that people can freely and interactively use it Seamless (and secure) delivery of services and applications
4 Characteristics of AmIAwareness ability of the system to locate and recognize objects and people, their locations, and their needs Intelligence allows the system to analyze the context, adapt to people that live in it, learn from their behavior, and eventually to recognize as well as show emotion Adaptable learn about the environment and the people within it in order to optimize their own behavior User Context
5 User Context Any information that can be used to characterize the user and her situation Coming from sensors Temporal and spatial location Environmental attributes Resources nearby Physiological measurements User preferences and profile Schedule, agenda Social context
6 An Example Scenario (from ISTAG)Maria lands to an airport in a Far Eastern Country The immigration officer replaced by a device Through its sensors, detects identities, performs visa and passport control (using Maria’s P-Com) A rented car waiting for her at the exit Her Hotel has been reserved by her personal software agent
7 Issues to be consideredIdentity information should be understandable by any authorized device Identity information P-Com Context servers Passport and visa information queries Machine proccesable Interoperable Context Ontologies should be developed
8 Issues to be consideredPrivacy Access should be limited to authorized entities The user should be able to state how much information to disclose and to whom Immigration device Location, visa, passport information Role or personal identity based privacy mechanisms
9 Issues to be consideredThe context servers needs to recognize the device type It should be possible to exploit context to discover and compose Web Services
10 Proposed System Architecture
11 Context Ontology Have formal specificationMachine processable Can be queried through query languages Define shared conceptualizations Captures consensual knowledge Enable knowledge sharing in an open and dynamic distributed system
12 Context Ontology Define all of the concepts in a taxonomic hierarchy Class Subclass Define the properties and allowed values (facets) Define the relationships among the classes properties Provides a means for intelligent agents to reason about the contextual information
13 Web Ontology Language OWLOWL is a semantic markup language being developed by the World Wide Web Consortium for publishing and sharing ontologies derived from DAML+OIL
14 Security and Privacy IssuesOntologies are stored in knowledge-bases Data coming from sensor devices Solar System (Minami & Kotz) Data coming from the context server Limited to authorized entities Should be possible to state how much information will be disclosed to whom
15 Security and Privacy IssuesView mechanism Define views on the user context and grant access rights to different users CREATE CLASS VIEW ScheduleOfMaria SUBCLASSOF Schedule SELECT X FROM ContextServer WHERE X.Name= “Maria” GRANT SELECT ON ScheduleOfMaria TO PersonalAgentOfMaria KAON server (http://kaon.semanticweb.org)
16 Exploiting User Context for Web Service DiscoveryFor selecting services in a context-sensitive manner Services should be discovered based on their semantic descriptions Agents should Query the context of the user Maps the preferences of the user with the properties of the services advertised
17 Web Service Discovery ebXML registry allows metadata to be stored in the registry through Classification mechanisms
18 An Example Travel OntologyTravelService Transportation Service Accommodation Service Entertainment Service AirTransportation ReserveAFlight BuyATicket Properties of the Generic Service Class originatingFrom destinationTo paymentMethod
19 Relating Services with OntologiesReserveAFlight originatingFrom destinationTo paymentMethod MyService
20 Service Ontology defined in class hierarchies through OWLAn example scenario ebXML Registry Service Ontology defined in class hierarchies through OWL Understands she doesn’t have a valid visa Checks her Profile Checks her Calendar Finds the service and its WSDL link Queries for the visa service of the Country Starts arranging her trip invokes Retrieves WSDL desc.
21 Service Ontology defined in class hierarchies through OWLAn example scenario Travel Service Transportation Service Accommodation Entertainment Air Transfer Land Transfer Sea Transfer Passport Visa Prefers air transfer, collects mileage from THY ebXML Registry Service Ontology defined in class hierarchies through OWL Domain expert Queries for the THY reservation service Finds the service and its WSDL link Checks her Profile Checks her Preferences consults invokes Retrieves WSDL desc.
22 Conclusions AmI combineUbiquity, context-awareness, intelligence and natural interaction There is a need for strong mechanisms for storing and processing context Context Ontologies
23 Conclusions To be acceptable AmI should provideSecurity Privacy Role-based access to context servers AmI should exploit user Context for reacting user needs automatically Web Service discovery and composition based on semantics
24 aVsonline.blogspot.com aVs 997 techfamilyThank you for your Attention Any Questions? aVsonline.blogspot.com aVs 997 techfamily