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Wireless service engineering


Why context-awareness

  • People react on same inputs differently depending on the context
  • To make the use of applications and services easier.
    • Computers do the work for user.
    • for example to help user find relevant information for given context
  • Added intelligence for automating processes


  • Several definitions by different groups doing research in the field
    • Dictionary: context == Surrounding conditions
  • Context adds semantic meaning to raw data
    • e.g. coordinate points turn to locations that have a contextual meaning (x=123, y= 150 maybe home as context)
  • Context can be defined for different objects
    • Person
    • Place
    • Object
  • Different kinds of context (just examples)
    • Location
      • Europe, Finland, Lappeenranta, Class room, Second row, third chair from left.
    • Time
      • 2005, Autumn, October, Thursday, 2 pm, 10 minutes after lunch
    • Activity
      • meeting, sleeping, watching tv,
    • Identity
      • Interests, Preferences, relations
    • Environmental
      • light level, noise level…
    • Behaviour
      • heart rate, role …

Sources for context

  • Fetching the context from user
    • Explicitly (requesting from customer)
      • User shouldn't be burdened too much
    • Implicitly
      • through communication with user device where user has given the data to application beforehand
      • e.g. calendar
        • work, vacation, meeting, busy….
  • Through context gathering and context reasoning
    • gathering data from different sources
      • integrated sensors
        • device speed, temperature, location…
      • environment sensors.
        • RFID tags providing information…
    • resoning the context based on the fetched raw data
      • Reasoning is the process of drawing conclusions from facts
      • Context reasoning can be explained as the task of deducing new information that is relevant to the use of applications and users, from the various sources of context data
        • 30 C, humid, stationary → at the pool
    • Complex process where lot of research is going on.
  • Determining new context from known contexts
    • User is on bed and heart rate is slow → user is sleeping
    • User has calendar note stating he is in meeting → user must be working
  • Fetching the context from context brokers (that may have done the reasoning)
    • Location provider
    • Context producers for MUPE (multiuser publishing environment) platform
    • Environment context broker.
  • Standardization is immature

Personal information as context

  • Application behaviour is altered based on user preferences
    • Preferences are the context
    • Personalisation
  • Preference information acquiring
    • Through registration.
    • From third party e.g. Liberty alliance
    • Profiling i.e. examining the customer behavior
  • Privacy

  • 3GPP GUP (Generic User profile)
    • designed for operator to manage user data.

Context-aware applications

  • The behaviour of application changes depending on the context.
    • Location based services
    • Device capability based applications
  • Examples
    • Location
      • Mobile phone don't ring at bath room
    • Activity
      • Mobile phone does not ring during meeting
    • Environment
      • Screen light turns on in the dark
      • Sound volume gets higher on noisy environment
    • Target
      • Communicating partner is online → message is transmitted using instant message
      • Communicating partner is not online → message is transmitted using email

Use of context data

  • Direct use
    • Get all the context data
    • Use the data as is or infer from the data the meaningful context to your application
  • Indirect use
    • Request the meaningful preprocessed context data from some context producer.
    • Request service adaptation data that has been aected by the context
  • Example: personal preferences
    • Direct use.
      • Request preferences from preference broker
      • Request context from context broker
      • infer what are the preferences for this context
    • Indirect use
      • Request preferences from preference broker
      • Preference broker requests the context from context broker
      • Preference broker delivers the context based preferences.

Context platform: Kontti

  • Reserch project on Context-aware service platform by VTT
  • Kontti platform supports context based information sharing and context based messages
    • Used content is adapted based on user preferences, device capabilities and network capabilites
  • context
    • time, place, social environment, technical environment, user denable situations
    • acquired either from user or for example LIF MLP protocol for location and UAProf for device capabilitis

Middleware for context awareness

  • RCSM [Yauet al., Pervasive Computing 1, 2002]
  • Confab [Hong & Landay, MobiSys2004]
  • GAIA for smart spaces [Campbell et al., Univ. of Illinois at Urbana-Champaign]
  • CORTEX [Blair et al. at Lancaster University]

Things to consider

  • Should my service/application take context into account
    • What are the contexts that are important?
  • Can I benefit on existing research on context and their meaning
    • activity areas
    • colours and lightning
  • Which sources I can use to gain context?
  • Should I participate in the course Ti5318000 Human-Centric Communication Services?
Last modified: 2013/07/01 14:41