Mobile Agent based Load
Balancing for RFID Middlewares
Author：Jian Feng Cui and Heung Seok Chae
Reporter ：郭瓊雯
Professor ：童曉儒 老師
Outline
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Introduction
Load balancing issues in RFID middlewares
Load balancing policies based on mobile agent
The proposed agent based approach for load
balancing of RFID middlewares
• Conclusion
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Introduction
• The paper exploit the issue of load balancing for
RFID middlewares, discuss load balancing policies
which are compliant to RFID middlewares and
propose a mobile agent based approach for RFID
middleware for load balancing.
• RFID Load Balancing Agent(RLBA) is proposed to
gather global and local workload information for
RFID middlewares and execute load balancing
strategy.
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Load balancing issues in RFID middlewares(1/2)
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Load balancing issues in RFID middlewares(2/2)
• Each RFID middleware receives tags information
from the connected reader.
– The information quantity depends on the number of readers
connected to it and the number of tags collected from those readers.
• RFID middleware has too many connected readers
or collects too many tags from them, it may make
the RFID middleware response delayed or even
broken down.
• Solve the problem：Redistributing the readers
connected to the heaviest loaded middleware to
other lighter loaded middlewares.
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Load balancing policies based on mobile agent(1/2)
• A set of policies to decide the design of mobile
agent based load balancing
– Information gathering policy：User can define a proper
frequency of information exchange. The number of the
readers connected to the RFID middleware or the
number of tags read from those readers are candidate of
workload in RFID middlewares.
– Initiation policy：Assume that a RFID middleware with
heaviest load initiate process of load balancing.
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Load balancing policies based on mobile agent(2/2)
– Job transfer policy：Determines when the
initiator should reallocate requests to other node.
– Selection policy：Determines which particular
job to reallocate.
– Location policy：Determines which node the
jobs should be reallocated to.
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Architecture of the proposed approach(1/2)
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Architecture of the proposed approach(2/2)
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RFID load balancing agent(RLBA)(1/5)
• The load information is organized as Middleware
Load Table(MLT).
• MLT gives load information of each RFID
middleware in the cluster.
• If load information changed, MLT will also be
updated immediately by RLBA.
• The loacal copy of MLT at cach middleware is
used by RLBA to determine the target middleware
where selected readers should be reallocated.
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RFID load balancing agent(RLBA)(2/5)
• The load information is organized as Reader Load
Table(RLT).
• RLT tracks reader ID and number of tags on each
RFID reader.
• Each RFID middleware owns one RLT.RLT is used
to decide which reader is to be reallocated in case
that local RFID middleware is overloaded.
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RFID load balancing agent(RLBA)(3/5)
• RLBA is composed of six components:
– Load Collector：When Load Collector arrives at
each node, it should check the load status of each
middleware and tell the latest global load
information to RFID middleware.
– Load Monitor：Collects local reader’s workload
information. It checks workload of local RFID
middleware periodically and updates RLT on
local hose.
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RFID load balancing agent(RLBA)(4/5)
• RLBA is composed of six components:
– Balancing Trigger：Decides load balancing
criteria and whether to perform load balancing or
not.
– Reader Chooser：Determines which readers to
be reallocated.
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RFID load balancing agent(RLBA)(5/5)
• RLBA is composed of six components:
– Middleware Chooser：Determines the
destination RFID middleware to which the
chosen readers are reallocated.
– Reader Reallocator：Reallocates reader to
destination.
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The detailed design of RLBA(1/2)
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The detailed design of RLBA(2/2)
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Conclusion
• This paper exploit the issues of load balancing for
RFID middlewares, discuss load balancing policies
which are compliant to RFID middlewares and
propose a mobile agent based approach for RFID
middleware for load balancing.
• A mobile agent, RFID Load Balancing
Agent(RLBA) is proposed to gather global and
local workload information for RFID middlewares
and execute load balancing strategy.
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Thanks for your listening!
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