Semantic Gadgets Pervasive Computing Meets the Semantic Web

Semantic Gadgets Pervasive Computing Meets the Semantic Web Reza Zakeri Sharif University of Technology

Outline Pervasive Computing, A Quick Review n Why we need such a thing like Mobile Internet for Pervasive Computing? n Where stands the Semantic Web? n A short introduction to DAML-S. n What are Semantic Gadgets? n 2

Pervasive Computing We have listened enough about it ; ) n But in a nutshell: n ¨ Interconnected devices and services. ¨ Promising a seamless integration of digital infrastructure into our lives. n Building an Active Space !!! 3

Mobility n n Mobility makes things different. Device location is a new dimension ¨ ¨ n Usage contexts and needs are different ¨ ¨ ¨ n More information about the user and the usage context available New applications & services are possible Awkward usage situations (e. g. , in the car while driving) Specific needs You are always “on” (= connected) Dilemma The Internet - by design - represents a departure from physical reality ¨ But mobility grounds services & users to the physical world ¨ 4

What we need: Mobile Internet n Access to services from handheld terminals ¨ n Context-sensitivity ¨ n Dynamic synthesis of content location is one dimension of a “context”, but there are others New Technologies ¨ Artificial Intelligence n n ¨ Semantic Web n n ¨ machine learning: automatic customization and adaptation automated planning: autonomous operation intelligent synthesis of content from multiple sources (ad hoc & on demand) explicit representation of semantics of data & services Ubiquitous Computing n a paradigm shift in personal computing 5

Semantic Web n Current WWW was built for humans, not for machines n “Semantic Web” is like a global KB Use of the WWW as an infrastructure Better security & privacy will allow us to reason about trust, enabling completely new kinds of services and businesses ¨ Content-with-semantics paves way for the use of software agents ¨ ¨ n Hyperlinks with meaning ¨ n Agents can navigate the WWW by following semantic links What will happen when data comes with semantics? ¨ ¨ ¨ Data from different sources can be combined New, perhaps unforeseen opportunities and functionality will result Machines can meaningfully use the WWW and perform tasks on our behalf (“machine-understandable” content) 6

Semantic Web 7

What we expect? Things should just work. n Devices should… n figure out what to do ¨ form communities ¨ collaborate ¨ n General Trend ¨ Semantic Services 8

DAML-S For semantic description of web services. n Models services as processes n ¨ n Atomic, Simple and Composite processes Virtual and physical functions can be abstracted as web services ¨ Providing a uniform view to all different kinds of functionality. 9

DAML-S versus WSDL 10

NRC/ATG Ubi. Comp Architecture n Agent-based approach to “smart environments” Agents represent devices, users, and the room ¨ Discovery and exchange of capabilities, goals, etc. ¨ RDF metadata as the basic representational framework ¨ n Simple architecture with the following components: ¨ Sensory agents n ¨ Manipulation agents n ¨ Represent devices which accept user input (speech, gestures, etc. ) Represent devices which are capable of causing physical actions such as dimming lights, closing shades, projecting slides, etc. Problem solving agents n n n Input “fusion”, goal formation Planning Action delegation to manipulation agents 11

NRC/ATG Ubi. Comp Architecture n Ad hoc connectivity ¨ Designed n to use a wireless, ad hoc network Layered architecture 12

Semantic Gadgets n Semantic Gadgets are about device and information interoperability. n Semantic Services are the key aspect of semantic web in the context of pervasive computing. n Semantic Gadgets Devices/applications that utilize the semantic web. ¨ Requires… ¨ n n n Service Discovery Contracting for use Composition of services 13

Semantic Gadgets n Combine ubiquitous computing & the Semantic Web Device capabilities and service functionality explicitly represented ¨ Everything is addressable (using URIs) ¨ Semantic Web is the basis for “semantic interoperability” ¨ n Critical components Connectivity: wireless, ad hoc networks + service discovery ¨ Representation: models of devices, services, users, environments, etc. ¨ Reasoning, learning, planning ¨ n Other useful technologies ¨ Sensors, context-awareness, mobile code, … 14

Semantic Gadgets: Device Coalitions n All devices advertise their services n A device can extend its functionality by discovering missing functionality offered by another device ¨ contracting the use of the service ¨ n Everything can be discovered ¨ including “reasoning services” or who is going to develop overall plans for integrating devices into larger, task-oriented “teams” 15

Semantic Gadgets: Coalition Formation n Abstract the physical world as “services” notion of “Web Services” is useful here ¨ no real distinction between physical and virtual functionality ¨ n DAML-S: Semantic Web Services modeling Web Services and their semantics using DAML+OIL ¨ addresses service discovery and composition ¨ 16

Conclusions n n n Semantic Gadgets are about device and information interoperability. Semantic Gadgets represent a useful join up of communication devices with PDAs and home appliances. Critical to the success of this idea is the existence or emergence of certain infrastructures World Wide Web as a ubiquitous source of information and services ¨ The Semantic Web as a more machine- and automation-friendly form of the Web. ¨ 17

References n O. Lassila and M. Adler. Semantic Gadgets: Ubiquitous Computing Meets the Semantic Web, In D. Fensel, J. Hendler, W. Wahlster, and H. Lieberman, editors, Spinning the Semantic Web, pages 363– 376, MIT Press, 2003. n A. Ankolekar, M. Burstein, J. R. Hobbs, O. Lassila, D. Mc. Dermott, D. Martin, S. A. Mc. Illraith, S. Narayanan, M. Paolucci, T. Payne, and K. Sycara. DAML -S: Web ervice Description for the Semantic Web, In I. Horrocks and J. Hendler, editors, The Semantic Web - ISWC 2002, Lecture Notes in Computer Science 2342, pages 348– 363. Springer Verlag, 2002. n Ora Lassila and Mark Adler. Semantic Gadgets: Device and Information Interoperability, in: Kalle Lyytinen & Yongjin Yoo (eds. ): Ubiquitous Computing Environment, Case Western Reserve University, 2003 18