Context Architectures Using Web Services Phd candidate

Context Architectures Using Web Services

• PhD Candidate:

• Alvaro E. Escobar

• Advisors:

• Dr. Maria Petrie

• Dr. Eduardo Fernandez

Agenda

• Review the following papers:

• [Fou06] D Fournier, S B Mokhtar, N Georgantas,VIssarny. “Towards Ad-hoc Contextual Services for Pervasive Computing”. Proceedings of the 1st workshop on Middleware for Service Oriented Computing (MW4SOC 2006) Melbourne, Australia
• [Bar05] J E Bardram. “The Java Context Awareness Framework (JCAF) – A Service Infrastructure and Programming Framework for Context-Aware Applications”. Centre for Pervasive Computing, Department of Computer Science, University of Aarhus. Denmark.
• [Dom07] KM Dombroviak, R Ramnath. “A taxonomy of mobile and pervasive applications ”. Proceedings of the 2007 ACM symposium on Applied computing. Seoul, Korea.
• [Bha05] R Bhatti, E Bertino, A Ghafoor. “A Trust-Based Context-Aware Access Control Model for Web-Services”. Distributed and Parallel Databases, 2005 - Springer.

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Main Idea:

• How to incorporate context-aware concepts into SOA to enable context-aware services for pervasive computing.

• Managing Context Information:

• managed by centralized system and devices are consumers of context in a specific physical environment (pervasive spaces).
• managed by devices so they have access to context in any environment.

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Taxonomy of Context Information:

• User Domain
• System Domain
• Environment (physical) Domain

• Context Representation:

• Key-Value models
• Markup models
• Graphical models
• Object-Oriented models
• Logic models
• Ontologies

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• User Domain Context:

• Provide knowledge to enable applications adapt to the profile of their users.
• Subjective: Includes user’s personality and psychology.
• User mood and feelings (fear, anger, sad…)
• Objective: Includes user’s personal information.
• Personal information (name, last name, birth date…)
• Physiology information (height, weight, health…)
• Agenda information (user activities over time)

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• System Domain Context:

• Describes digital, software and hardware resources available to users.
• Processing power
• Hardware components
• Network interfaces
• Storage
• Software components

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Environmental Domain Context:

• Deals with the description of location and of conditions of the physical environment.
• Physical geography (GPS coor, room, building….)
• Physical conditions (windy, sunny, rainy…)
• Chronology (time, time zone, time of the day)

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Context Representation :

• Key-Value models: use a set of attributes and their associated values.
• Markup models: structure context into a hierarchy using tags.
• Graphical models: express relationships between context entities.
• Object-Oriented models: structure context into object classes and their implicit relationships.
• Logic models: express context in terms of facts and rules.
• Ontologies: combination of logic models and O-O models they structure context into object classes and their explicit relationships.

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Context Management :

• Initially application-specific context managers (limited re-use; built for app-specific context).
• Location-aware systems like Active Badge and Cyberguide.
• Then dedicated Context Frameworks allowed more general (re-usable) context managers.
• Context Toolkit (Dey), Contextors (Coutaz)
• JCAF (Bardram)

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06]

• Context Management (continue):

• Lately is the Server-Oriented approach to context managers ( deployment of context servers within the network).
• SOCAM (Service-Oriented Context Aware Middleware)
• CoBra (Context Broker Architecture)
• More recently the P2P architecture of context managers (devices responsible for managing subset of context).
• AWARENESS project, where mobile and desktop devices acquire, interpret and exchange context even in the absence of a context server.

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06] Context Sources

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06] Context Consumption

Towards Ad-hoc Contextual Services for Pervasive Computing[Fou06] Context-aware Services

Conclusions

Towards Ad-hoc Contextual Services for Pervasive Computing

• References:

• [Bel03] P. Bellavista, A. Corradi, R. Montanari, C. Stefanelli, “Context-Aware Middleware for Resource Management in the Wireless Internet”, IEEE Transactions on Software Engineering. Vol. 29, No. 12, December 2003. Page 1086.
• [Bra01] T. Bray. What is RDF? http://www.xml.com/pub/a/2001/01/24/rdf.html,
• January 24, 2001
• [Cha04] T. Chaari, F.Laforest, A. Celentano. “Design of Context-Aware Applications. Based on Web Services”. LIRIS. Dipartimento di Informatica. INSA Lyon, France
• [Che03] H. Chen, T. Finin and A. Joshi. “An Ontology for Context-Aware Pervasive Computing Environments”. IJCAI Workshop on Ontologies and Distributed Systems, IJCAI 2003, Acapulco, Mexico, 2003.
• [Cor04] A. Corradi, R. Montanari, D. Tibaldi, “Context-Based Access Control Management in Ubiquitous Environments”, Network Computing and Applications, Proceedings of the Third IEEE International Symposium on (NCA'04), August 30 - September 01, 2004, Boston, MA.
• [Dey01] A. Dey, G. Abowd, D. Salber, “A Conceptual Framework and a Toolkit for Supporting the Rapid Prototyping of Context-Aware Applications” - Human-Computer Interaction, 2001 - Lawrence Earlbaum
• [Fer07] E. B. Fernandez, A. E. Escobar, M. Larrondo-Petrie. “Contexts and Context-Based Access Control”. The Third International Conference on Wireless and Mobile Communications, ICWCF’07, March 2007. Guadeloupe, French Caribbean.
• [Fer05] E.B. Fernandez, T. Sorgente, N. Delessy, and M.M.Larrondo-Petrie, "A survey of web services security", Technical report to DISA (Defense Information Systems Agency), grant # ?????, 2005
• [Fer04] E.B. Fernandez, "Web services security: An overview of standards and industrial practice", 2004
• [Gu04] T. Gu, X.H. Wang, H.K. Pung, D.Q. Zhang. “An Ontology-based Context Model in Intelligent Environments”, Proceedings of Communication Networks and Distributed Systems, 2004.
• [Hel02] A. Held, S. Buchholz, A. Schill, "Modeling of Context Information for Pervasive Computing Applications", In Proceedings of the 6th World Multiconference on Systemics, Cybernetics and Informatics (SCI), Orlando, FL, July 2002.
• [Rae05]M. Raento, A. Oulasvirta, R. Petit, H. Toivonen. “ContextPhone: A Prototyping Platform for Context-Aware Mobile Applications”. IEEE Pervasive Computing, 2005.
• [Sil05] J. Siljee, S. Vintges, J. Nijhuis. “A Context Architecture for Service-Centric Systems”. Context Modelling and Management in Ambient-Aware Pervasive Environments. LoCA 2005, Oberpfaffenhofen, Germany, May 12-13, 2005.
• [W3C04] http://www.w3.org/TR/ws-arch/

Agenda

• Review the following papers:

• [Fou06] D Fournier, S B Mokhtar, N Georgantas,VIssarny. “Towards Ad-hoc Contextual Services for Pervasive Computing”. Proceedings of the 1st workshop on Middleware for Service Oriented Computing (MW4SOC 2006) Melbourne, Australia
• [Bar07] J E Bardram. “The Java Context Awareness Framework (JCAF) – A Service Infrastructure and Programming Framework for Context-Aware Applications”. Centre for Pervasive Computing, Department of Computer Science, University of Aarhus. Denmark.
• [Dom07] KM Dombroviak, R Ramnath . “A taxonomy of mobile and pervasive applications ”. Proceedings of the 2007 ACM symposium on Applied computing. Seoul, Korea.

Future Work