DBGlobe: A Data Centric Approach to Global Computing

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DBGlobe A Data Centric Approach to Global
Computing

• 3rd Meeting
• Athens, November 29, 2002
• George Samaras
• Chara Skouteli
• UCY

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Context Aware Applications

• How we define context
• Context is any information that can be used to
  characterize the situation of an entity.1
• An entity is
• a person,
• place,
• or object
• that is considered relevant to the interaction
  between a user and an
• application, including the user and application
  themselves.

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Context Information

• Almost any information available at the time of
  an interaction can be seen as context
  information. Some examples are
• identity
• spatial information - e.g. location, orientation,
  speed, and acceleration
• temporal information - e.g. time of the day,
  date, and season of the year
• environmental information - e.g. temperature, air
  quality, and light or noise level
• social situation - e.g. who you are with, and
  people that are nearby
• resources that are nearby - e.g. accessible
  devices, and hosts
• availability of resources - e.g. battery,
  display, network, and bandwidth
• physiological measurements - e.g. blood pressure,
  hart rate, respiration rate, muscle activity, and
  tone of voice
• activity - e.g. talking, reading, walking, and
  running
• schedules and agendas

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Challenges

• Capture
• Inputs from system
• Inputs from devices
• Inputs from users
• Represent
• Use of xml schema
• Efficient taxonomy
• Process contextual data
• Queries on metadata
• Data Mining
• Create or discover a relationship between them

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Context-Aware Applications

• Find nearby resources.
• This can include input and output devices
• printers, displays, speakers, facsimiles, video
  cameras, thermostats, etc.
• location information of the client is required.
• Create local network communities.
• Obtain regional information in the ad-hoc
  network.

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DBGlobe proof of- content Prototype

• The innovative features of our prototype include
  working example of
• Concept of the ad-hoc databases
• Use of metadata to include location and user
  preferences in dynamic query processing
• Co-ordination and co-operation of autonomous
  entities.
• Information Discovery and Querying

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Global Communicator Middleware

• Defines the communication level between
  context-aware applications and DBGlobe system
• Provides
• Access to DataHandler
• Access to Available Services of the DBGlobe
  System
• Disconnection Support
• Application Data sharing between context-aware
  applications
• Caching
• Should this middleware be part of the DBGlobe
  system??

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Communication Flow
PMO
Application Proxy
Application Interface Modules
Application Function Modules
Global Communicator Middlware
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Global Communicator middleware
Communicator Finds the location of remote
objects Gives a reference to the appropriate
object.
UserAgent Represents user in the
application Keeps metadata information about
user Disconnection support
Communities can be divided to several categories
and user can join them.
Queries Results Database to temporarily store
search results of a query
Application Metadata Database which holds
metadata for users or devices necessary for the
application.
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Applications
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Suggested proof of content prototype
DB-Communicator

• DB-Communicator
• With DB-Communicator users will be able to
• Search for data in DBGlobe system (information
  discovery and querying)
• Create communities or join communities (concept
  of ad-hoc database)
• To share data with other people who join the
  community (co-ordination and cooperation with
  autonomous entities)
• To define dynamic request according to their
  context information
• Push data
• Pull data
• favorite services (service discovery)
• Make request for a service
• Easy to extend by using the available services of
  the DBGlobe system.

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Communication Flow Request for a service
PMO
DB-Communicator Proxy
Application Interface Modules
Application Function Modules
Global Communicator Middlware
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Application ParadigmSpotme!

• Main functionality
• Locate my friends and let me communicate with
  them
• Aims to show the capability of DBGlobe system to
  find services and provide them to applications.

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Communication Flow
PMO
Spotme Proxy
Application Interface Modules
Application Function Modules
Global Communicator Middlware
Application users
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Engineering Issues

• For remote access to objects we use voyager
  platform
• In order to step forward we need the main modules
  API
• Login/Registatration
• Service Description Method
• Service Communication Method
• DataHandler interface
• PMOs coordination mechanism
• Interface Module API

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Publications under DBGlobe

• 2 G. Samaras, C. Spyrou, E. Pitoura, View
  Generator (VG) A Mobile Agent Based System for
  the Creation and Maintenance of Web Views, 7th
  IEEE Symposium on Computers and Communications,
  Taormina, Italy July 2002.
• 3 George Samaras, Constantinos Spyrou,
  Evaggelia Pitoura, Marios Dikaiakos, Tracker A
  Universal Location Management System for Mobile
  Agents. Proc. The European Wireless 2002
  Conference, Next Generation Wireless Networks
  Technologies, Protocols, Services and
  Applications, pp. 572-580, Florence, Italy,
  February 25-28, 2002.
• 4 George Samaras, Christoforos Panayiotou, "A
  Flexible Personalization Architecture for
  Wireless Internet Based on Mobile Agents", Proc.
  6th East-European Conference on Advances in
  Databases and Information Systems (ADBIS 2002),
  September 2002, Bratislava, Slovakia.
• 5 George Samaras, Christoforos Panayiotou,
  Wireless Portals for the Mobile User", ICDEE
  2003, Demo

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References

• 1 Mari Korkea-aho Context-Aware
  Applications Survey ,Helsinki University of
  Technology , 2000

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• Thank you!!!
• Merry Christmas