WP1'4: Context aware content delivery

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WP1.4 Context awarecontent delivery

• Fredrik Kilander KTH/ICT (DSV)
• Johan Eliasson (DSV)
• Prof. Carl Gustaf Jansson

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Interest areas

• Support users moving within heterogenous wireless
  infrastructures
• Adaptive user-centric Internet services
• Dynamic reconfiguration
• Context information
• User (perception of) control

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Focus of work

• Create a complete context system
• Simple sensors
• Simple context (no ontology)
• Simple dissemination
• User extensibility
• Thin interface layers sensor//system//app

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Design choices - sensors

• Re-use systems for GSM (Li Wei) and WiFi
  positioning (Spots/M. Jonsson)
• Short range motion detection using inexpensive
  web cam and Internet shareware (office space)
• Keyboard and mouse activity with modified
  C-example (PC space)
• Second order sensors in remote software

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Design choices - system

• Implemented as a web service
• HTTP GET for sensor updates
• Apache web server
• mySQL database
• RSS (XML) distribution (polling)

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Open Context Aggregation and Dissemination
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Update format

• http//su.se/context.php?idSpot1plocationvOf
  fice
• Id the sensor identifier
• P the parameter name
• V the value string
• Security model associated with the sensor
  identifier

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System output

• Sensor values available as XML
• Applications poll using RSS
• XML and RSS are well supported
• Context refinement externalized in second order
  sensors

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Applications

• Skype status message
• Automatic email .signature update
• Second order sensor (refiner) acts both as
  application and sensor

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Findings

• Open architecture supports extensibility
• An integrated security model is highly
  recommended
• Small applications (Java) due to strong XML and
  Web support
• Ontology issues remain in simple context data

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End