Semantic Web Interaction

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Semantic Web Interaction
Wireless Agent-based

• Heikki Helin ltHeikki.j.Helin_at_teliasonera.comgt
• Principal Researcher, PhD
• Emerging Technologies and Innovations,
  TeliaSonera Finland

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Presentation Outline

• About TeliaSonera
• Motivation
• In which field we are playing
• What we are trying to achieve
• Agent-based architecture for nomadic environments
• Agents architecture for such environments
• Communication framework for wireless
  communication
• Ontologies for nomadic environments
• On-going (or soon-to-be-started) research
  projects
• National, EU/FP6
• Summary

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TeliaSonera

• The Nordic and Baltic leader in
  telecommunications
• The merger between Telia and Sonera became a
  reality on December 9, 2002
• Listed on the Stockholm Exchange, the Helsinki
  Exchange and Nasdaq Stock Market in the USA
• Net sales (pro forma) in 2003 amounted to SEK
  81,772 million (EUR 9,010 million)
• The number of employees was 26,000 on December
  31, 2003
• RD personnel 1000

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The markets of TeliaSonera International
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Motivation

• New wireless Internet services for our mobile
  (and fixed) customers
• Not only new services, but also enhance old
  ones to give better user experience
• And do that
• faster,
• easier,
• cheaper, ...

gt To attract new customers, but more
importantly keep the old customers (and at the
same time do some academic research)
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Background

• Multi-agent system implementing a middleware
  providing (agent-based) applications with tools
  for adaptation in a nomadic environment
• Nomadic environments enable new ways to access
  services
• ? anywhere, at any time, and using any device
• Challenges that need to be addressed
• Varying QoS of the wireless networks
• Limitations of mobile devices
• Contextual variability (location, time, user
  preferences, ...)
• Adaptation to environment is the key issue

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Mobile/Wireless Environment

• Typical characteristics
• Low throughput, long delays, unreliable, ...
• Variability
• Disconnected mode of operation is the most common
  state
• Different kind of (wireless) networks
• Seamless roaming will be important in the future
• Actors (agents) in nomadic environments should be
  aware of these issues
• Context-awareness (not only location)
• Currently we are mainly considering long thin
  networks
• GSM, HSCSD, GPRS, UMTS, ...
• But not excluding WLANs, BT, LAN, xDSL, ...

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Agents in Nomadic Environments

• Suitable for complex environments
• Internet is a complex environment...
• Wireless Internet is even more complex...
• Invisible Internet...

Ambient networks
Semantic Web
QoS
Peer-to-peer
Intelligent P2P
Pervasive Computing
Ubiquitous Computing
Ontologies
Ad hoc networks
Distributed Artificial Intelligence
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FIPA Agent Platform
DF Directory Facilitator AMS Agent Management
System ACC Agent Communication Channel
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(FIPA) Nomadic Application Support
Knowlegde Sharing
Controlling monitoring
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(FIPA) Nomadic Application Support
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Agent Communication Wireless World
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Layered model of agent communication
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Message Transport
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Message Transport

• How messages are transferred between agents
• Desiderata
• Reliability
• Efficiency
• Dynamic adaptation
• Issues
• Performance problems
• Terminal mobility
• Thin clients

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MTP Results 11 9600bps (300ms)
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MTP Results 11 115200bps (300ms)
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Message Envelope
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Message Envelope

• FIPA specific layer
• Defines how messages are delivered
• independent of message transport protocols
• Encoding options
• XML, Bit-efficient, IIOP/IDL, Binary-XML, Java
  Objects,
• Bit-efficient encoding similar to bit-efficient
  ACL

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Message Envelope
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ACL Layer
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ACL Encoding

• Options
• String (s-expression), XML, Bit-efficient
• Binary-XML (w/ special encoding tokens), Java
  Objects
• Bit-Efficient encoding is the most efficient
• Space-efficient
• ...by definition
• Time-efficient
• much faster
• nice for every application not only for wireless
• necessity for
• high performance applications
• highly utilized servers
• simple parser ? appropriate for thin clients

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ACL Encoding (request conversation)
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ACL Encoding
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Content Language Layer
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Content Languages

• FIPA-SL
• All-purpose content language
• S-expression (w/ deflate), XML, Binary-XML (w/
  special tokens)
• FIPA-CCL
• Language for constraint satisfaction problems
• XML Binary-XML
• Results similar to those of message envelope and
  ACL

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Conversation Layer
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Conversation Layer

• Optimizing/modifying existing conversation
  protocols?
• Developing new conversation protocols?
• Selecting conversation protocol based on current
  environment
• low bandwidth ? simple protocol
• ? not so good end result
• more bandwidth ? more complicated protocol
• ? better end result

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Ontologies in Wireless World
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Ontologies

• An ontology is an explicit description of a
  domain
• Concepts
• Wireless network, GSM, GPRS,
• Properties and attributes of concepts
• Each Network will have Operator, Location,
  Properties,
• Every IEEE802.11a is a WLAN
• Constraints on properties and attributes
• The name of an Operator is a string
• GSM network code consist of CountryCode and
  NetworkID
• Individuals (often, but not always)
• The GSM network operated by TeliaSonera in
  Finland
• An ontology defines
• a common vocabulary
• a shared understanding

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Cant we just use XML?
For machines, a typical web page looks like this

• XML is not enough
• Ontological modeling primitives missing
• RDF/RDFS is better, but
• Only a weak semantic interpretation
• No inference model
• OWL (Web Ontology Language)
• Extends RDFS
• Additional vocabulary along with a formal
  semantics
• More vocabulary for describing properties and
  classes
• Relations between classes (e.g. disjointness)
• Cardinality (e.g. "exactly one")
• Equality
• Richer typing of properties
• Characteristics of properties (e.g. symmetry)
• Enumerated classes

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XML Helps...
XML allows meaningful tags to be added to parts
of the text

• ltnamegt
• XML is not enough
• Ontological modeling primitives missing
• lt/namegt
• ltaddressgt
• RDF/RDFS is better, but
• Only a weak semantic interpretation
• No inference model
• lt/addressgt
• ltcvgt
• OWL (Web Ontology Language)
• Extends RDFS
• Additional vocabulary along with a formal
  semantics
• More vocabulary for describing properties and
  classes
• Relations between classes (e.g. disjointness)
• Cardinality (e.g. "exactly one")
• Equality
• Richer typing of properties
• Characteristics of properties (e.g. symmetry)

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XML ? Machine Accessible Meaning
To machines, the tags looks like this

• ltnamegt
• XML is not enough
• Ontological modeling primitives missing
• lt/namegt
• ltaddressgt
• RDF/RDFS is better, but
• Only a weak semantic interpretation
• No inference model
• lt/addressgt
• ltcvgt
• OWL (Web Ontology Language)
• Extends RDFS
• Additional vocabulary along with a formal
  semantics
• More vocabulary for describing properties and
  classes
• Relations between classes (e.g. disjointness)
• Cardinality (e.g. "exactly one")
• Equality
• Richer typing of properties
• Characteristics of properties (e.g. symmetry)

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Web Ontology Languages

• Ontologies have been active research area for a
  long time
• Web ontology languages
• Provide web-friendly representation language
• Typically based on RDF Schema
• OWL is currently W3C Recommendation

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Web Ontology Languages (cont.)

• XML is not enough
• Ontological modeling primitives missing
• RDF/RDFS is better, but
• Only a weak semantic interpretation
• No inference model
• OWL (Web Ontology Language)
• Extends RDFS
• Additional vocabulary along with a formal
  semantics
• More vocabulary for describing properties and
  classes
• Relations between classes (e.g. disjointness)
• Cardinality (e.g. "exactly one")
• Equality
• Richer typing of properties
• Characteristics of properties (e.g. symmetry)
• Enumerated classes

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Need for Ontologies in Wireless World
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Wireless Network Ontology - Motivation

• Machine-readable ( understandable) descriptions
  of networks
• Currently available only for humans
• 3rd party service providers
• Available networks at Gent?
• Available networks at this Hotel?
• Future applications
• Context-aware
• Available networks near here?
• Best available network?
• Available networks near my friend?
• Any application requiring information about
  (wireless) networks or their properties
• Almost all wireless world applications?

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Wireless Network Ontology Overview

• Core Concepts
• Network -gt Wireless Network -gt GSM Network -gt ...
• Operator
• (Location)
• ...
• QoS Concepts
• Throughput, delay, rtt,
• Services
• GSM Services
• Supplementary services, Tele services,
• WLAN Services
• ...

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Wireless Network Ontology Core Concepts
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Wireless Network Ontology Services
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Wireless Network Ontology QoS Concepts
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Related Projects _at_ TeliaSonera
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Related projects _at_ TeliaSonera

• EU/FP6 projects
• Ambient Networks (IP), Magnet (IP)
• CASCOM (Strep)
• National projects
• CAPNET
• Fuego Core
• Intelligent Web Services

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CASCOM Overview

• Context-Aware Business Application Service
  Co-ordination In Mobile Computing Environments
• FP6/2 Strep project
• 414 PM/3 years
• 8 partners
• Project goal
• Develop, implement, validate, and trial of
• Agent-based service coordination infrastructure
  for
• Innovative semantic Web service discovery,
  composition, execution
• Across mobile and fixed Peer-To-Peer service
  networks

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CASCOM Main ST Innovations

• Generic Service Agent Architecture and Prototype
  Demonstrator
• CASCOM Service Coordination Means
• Declarative Service Description
• Flexible Service Matching
• Dynamic Service Composition
• Secure Service Execution Monitoring
• CASCOM Intelligent Service Agents
• Service Agent Platform for Nomadic Computing and
  Ad-Hoc P2P Communication
• Context-Aware Service Provisioning
• Dynamic Service Agent Coalitions

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CASCOM Use Case Scenario

• Ad-Hoc Emergency Medical Care and Transport
• Medical information
• Patient transport
• Insurance coverage

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Intelligent Web Services (IWebS)

• Semantic yellow page services
• How the user finds correct service(s)?
• How the service provider advertises the service
  it provides?
• Dynamic content
• Service composition
• Support for different terminals
• Desktop, mobile, ...
• http//www.cs.helsinki.fi/group/iwebs/

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IWebS Sample Scenario
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Summary

• Nomadic environments introduce challenges, such
  as varying QoS, variations and limitations of the
  mobile devices, as compared to desktop
  environments
• Device independence and adaptation are key issues
  when designing and implementing services for such
  environments
• Agent architecture with efficient communication
• Ontologies
• (Wireless) networks
• QoS
• Other domains need conceptualization as well
• Services
• Users
• Preferences, etc.
• Devices

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More information

• Heikki Helin and Mikko Laukkanen Performance
  Analysis of Software Agent Communication in Slow
  Wireless Networks. In Proceedings of the 11th
  International Conference on Computer
  Communications and Networks (ICCCN'02), October
  2002
• Heikki Helin and Mikko Laukkanen Wireless
  Network Ontology. In WWRF9, July 2003
• Heikki Helin Supporting Nomadic Agent-based
  Applications in FIPA Agent Architecture. PhD
  Thesis. University of Helsinki, Finland. February
  2003.