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Multi-Agent Systems for Distributed Data Fusion
in Peer-to-Peer Environment

• Smirnova Vira

Cheese Factory/ 19.12.2002
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Main goals

• To design a new model for fault-tolerant and high
  availability of Distributed Sensor Networks and
  data fusion
• To modify existing data fusion process into a new
  one by combining multi-agent systems with P2P
  environment
• To consider the behaviour of the system in common
  failure conditions
• To compare complex distributed systems such as
  DSN, MADSN and P2PDSN

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Multi-agent systems

• are collections of several computational
  entities, called agents, interacting with one
  another
• MAS can be characterized as
• each agent has incomplete information or
  capabilities for solving the problem and, thus,
  has a limited viewpoint,
• there is no global control in the system,
• location of data is decentralized and
• computation is asynchronous.

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AOIE and PAGE paradigms
P- Percepts A Actions G- Goals E - Environment

• A Agent
• O Organization
• I Interaction
• E Environment

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Distributed Sensor Networks

• General DSN (architecture)

example of one cluster
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MADSN Mobile Agent based Distributed Sensor
Network

• is an extension of DSN that is based on applying
  mobile agent technologies The difference between
  them is that MADSN is an improved DSN
  architecture that uses mobile agents

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Data Fusion I

• Centralized DF is characterized by a hierarchy of
  nodes, in which all information is passed up the
  hierarchy to a centralized fusion node

• disadvantages
• low availability of the fused picture at the
  lower level nodes
• a single point of failure in the system
• limits the ability of the individual participants
  to operate independently
• can require significant communications bandwidth

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Data Fusion II

• Decentralized DF is charecterised by system
  that consists of a network of sensors nodes each
  with its own processing facility.

• advantages
• higher availability of the fused picture at the
  lower level nodes
• no single point of failure in the system
• no global knowledge of sensor network topology
  (just knowledge about neighbors)
• bandwidth requirements are less then CDF

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Peer-to-Peer

• By realizing DDF I have used some of ideas from
  P2P systems.
• P2P collection of distributed resources
  connected by a network.

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P2PDSN

• The whole model consists of several major
  functional modules
• collecting of measurements from sensors,
• analyzing of collected data,
• representation of data to user and
• controlling and monitoring the current state of
  Distributed Sensor Network

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Agents and their Organization in the System

• 1 (CA SA) Control messages
• 2 (SA CA) Sensors measurements
• 3 (CA AA) Push measurement data
• 4 (AA CA) Push analyzed data
• 5 (VA CA) Request for getting analyzed
  data, Request for commands
• 6 (CA VA) Analyzed data
• 7 (user VA) Users requests and commands
• 8 (VA user) Representation of analyzed
  data

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Interactions between agents

• the idea of interaction is not only transfering
  bits through channel, it means to reach the
  high-level interoperability via communication!

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States of P2PDSN

• Each of the presented agents has their own tasks,
  responsibilities and goals which depends ot their
  state
• A state of agent is controlled by the arrival and
  content of the message

Example of state diagram
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Deficiencies in System States

• There are four main categories that were not
  taken into account in the design and require
  further research
• 1.      Tampering of agents,
• 2.      Tampering of messages,
• 3.      Unreliability of the network and
• 4.      The implementation of the system

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Comparison between DSN, MADSN and P2PDSN models
 
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Conclusion

• was developed a model that allows disparate
  systems to interact automatically with one
  another in order to optimize data fusion and data
  management processes
• was described in the thesis multi-agent system
  suits well for realizing P2PDSN system because of
  the desired characteristics it possesses which
  allow agents to represent a peers due to their
  autonomous and social nature

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Conclusion (2)

• From an engineering point of view the system is
• fault-tolerant because there is no a single
  point of failure,
• high-available, because there are several copies
  of the same data but in different locations,
• extensible because new peers (agents) can be
  added dynamically and
• flexible according to previous benefits.

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Further work

• Unanswered questions are
• the security,
• loosing of messages,
• loops,
• denial of services and technical possibilities of
  devices that can be used in the system.
• Also the system has to be implemented for more
  detail testing and verifying that all the
  components work together.

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Thank you for your attention!!!