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

• 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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– 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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Load balancing policies based on mobile agent(2/2)

Architecture of the proposed approach(1/2)

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Architecture of the proposed approach(2/2)

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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