A Location Model for Pervasive Computing Environment 3rd Pervasive Computing and Communication, PerC

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A Location Model for Pervasive Computing
Environment(3rd Pervasive Computing and
Communication, PerCom 2005) Ichiro
SatohNational Institute of Informatics

• Lee, Jong Gun (jglee_at_an.kaist.ac.kr)
• AN Lab., KAIST

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Table of Contents

• Introduction
• World model
• Prototype implementation
• Experience
• Conclusion Future work

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Introduction
Location
physical
logical
GPS
?
outdoor
central database
Location model for managing location-based and
personalized services in indoor setting
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Requirements of PCE
PCE Pervasive Computing Environment
Mobility
Availability
Heterogeneity
Absence of centralized database
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Design principles of PCE
Virtual counterparts
Digital representations of physical entities or
spaces
Local Interaction
Communicate with others of local area (scope)
Unified view
Not distinguish between physical entities, spaces

Extensibility
Dynamically deployed software as well as
on-demand
Sensor-independence
support various kinds of sensors (Tracking and
positioning system)
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World Model
- Component Relationship Model - Virtual
Component - Aura Component - Service Component -
Proxy Component
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Component relationship model

• Virtual counterpart
• component is mapped to virtual counterpart
• Containment relationship
• according to spatial containment relationship
• contained at most one component
• mobility
• Movement range

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Components

• Virtual component (VC)
• representation
• Aura components (AC)
• scope
• Proxy component (PC)
• bridge,
• maintain of subtree,
• execution of service
• Service component (SC)
• software module

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Virtual component

• Containment relationship model
• Dont distinguish between entities and places
• e.g., a car and a person

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Aura component

• In aura,
• the connection between two objects in a
  virtual-reality
• become possible
• when the object scopes collide or overlap

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Proxy component

• PCS (PC for service provider)
• doesnt have any computing capabilities
• PCL (PC for legacy device)
• has computational capabilities

PC vs. TV
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Implementation
- Components - Component Management System -
Location-Sensor Management System - Performance
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Components

• All components are defined as
• subclass of abstract class Component

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Component management system

• Component migration system
• Transformation of the tree structure
• Through TCP connection
• Only within the reachable distance

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Location-sensor management system

• Monitoring locations sensors
• Location-based deployment of components

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Performance

• Suns J2SE v1.4 (for prototype)
• MobileSpace mobile agent system
• (for commercial locating systems, RFIDs)
• Pentium mobile 1.6GHz (for computing devices)
• Migration of 4KB component
• 390msec (TCP connection 41msec)

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Location-based navigation system

• PDA enters a room
• RF-tag reader detects the presence of tag
• LSM tries to discover the component bound to the
  PDA
• LSM informs the VC (room) about the capabilities
  of PDA and PCS
• VC deploys a SC at PCS
• PCS forwards the SC to the PDA
• PDA displays the map of the room

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Conclusion future work

• Conclusion
• location model for developing and managing
  context-aware services in pervasive computing
  environment
• Dynamically organized like a tree
• Unified view of the locations of all kinds of
  things
• Future work
• more applications
• this model with other languages
• incorporation existing spatial database
• software testing for location-based mobile
  computing

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References

• 1 Ichiro Satoh, A Location Model for Pervasive
  Computing Environment, Pervasive Computing and
  Communication (PerCom), 2005
• 2 Ichiro Satoh, A Spatial Model for Ubiquitous
  Computing Services, The Institute of
  Electronics, Information and Communication
  Engineers (IEICE), 2005