A Service-Oriented Peer-to-Peer System for University Library Resource Sharing

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A Service-Oriented Peer-to-Peer System for
University Library Resource Sharing

• Presented By Chandana Kancherla
• Supervisor Dr. Haiping Xu
• Spring 2005 UMass Dartmouth

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Outlines

• Peer-to-Peer Systems
• Web Services
• System Requirements
• System Architecture
• UML Diagrams
• Implementation
• Future Scope

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Peer-to-Peer Systems

• File sharing P2P applications focus on storing
  and retrieving information from various peers in
  the network
• The model that popularized this class of
  application is the content exchange model
• A P2P application should be able to locate other
  peers in the network.
• Once an application is able to locate other
  peers, it should be able to communicate with them
  using messages.
• P2P systems consider that all nodes or peers are
  equal for sharing information.

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Peer-to-Peer Systems Contd.

• There are two types of P2P architectures Pure
  and Hybrid.
• Pure P2P In this model, there is no main
  server. Every peer is a client as well as a
  server.
• Hybrid P2P In this model, there is a special
  server that maintains a database and performs
  some administrative functions.

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Web Services

• A Web service is accessible over the web. Web
  services communicate using platform-independent
  and language-neutral web protocols.
• A Web service provides an interface that can be
  called from another program. The Web service
  interface acts as a liaison between the web and
  the actual application logic that implements the
  service.
• Web services support loosely coupled connections
  between
• systems. The web service interface adds a
  layer of abstraction to the environment that
  makes the connections flexible and adaptable.

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Web Services Contd.

• Three XML-based technologies have emerged as the
• standards for Web services
• Simple Object Access Protocol (SOAP) defines a
  standard communications protocol for Web
  services.
• Web Services Description Language (WSDL) defines
  a standard mechanism to describe a Web service.
• Universal Description, Discovery and Integration
  (UDDI) provides a standard mechanism to register
  and discover Web services.

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Requirements

• Design and implement a service oriented
  Peer-to-Peer system for University Library
  Resource sharing.
• When the user wants to perform a remote search on
  a peer from another network then the peer can
  select a peer from a remote network and send a
  request and that respective remote peer will
  perform a local search within its network and
  return the result to the requestor.
• The result of a remote search will contain all
  the URLs and the names of the Universities
  (hosts) that have the requested resource and the
  user will be allowed to choose from where he/she
  wants to download the book.
• Pure P2P architecture is used here which is a
  major feature since it eliminates the risk of
  single point of failure.

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Architecture
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Class Diagram
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Class Diagram Contd.
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Sequence Diagrams

• Local Search

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Sequence Diagrams Contd.

• Remote Search

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Sequence Diagrams Contd.

• Upload

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Sequence Diagrams Contd.

• Download

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Programming Platform - J2EE

• The J2EE platform uses a distributed multi-tiered
  application model for enterprise application
• Web services are web-based enterprise application
  that use open, XML-based standards and transport
  protocols to exchange data with calling clients
• The J2EE platform provides the XML APIs and tools
  you need to quickly design, develop, test, and
  deploy web services and clients running on
  Java-based or non-Java-based platform
• JAX-RPC stands for Java API for XML-based RPC.
  JAX-RPC is a technology for building web services
  and clients that use remote procedure calls (RPC)
  and XML.

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Implementation

• Local Search
• The program gets the search details from the user
  interface.
• An object of the class Request is created with
  all the search details specified by the user.
• The object Request is then serialized into an XML
  string
• The Search method is called on the local hosts
  with the XML string as parameter
• The search call returns another string that
  contains the serialization of the Object Reply
  which contains details of the book.
• The program unserializes the string for the
  object Reply.

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Implementation Contd.

• Remote Search
• Similar to Local search except that instead of
  the method local search the method Remote Search
  is called.

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Implementation Contd.

• Upload
• An instance of the AdminI Interface for the local
  host is created.
• The method uploadBook is called with the string
  that contains the serialization of the object
  Book.
• The method returns the result of upload and the
  program displays the result to the user.

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Implementation Contd.
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Implementation Contd.

• Download
• The program retrieves the host of the book
  selected from the object Reply.
• An instance/local stub of the PeerServerI
  interface is created
• The method download of PeerServerI is called with
  the book id (retrieved from the object Book) as
  the parameter.
• The method call returns the string that contains
  the serialization of the object Book.
• The program unserializes it and stores it to the
  specified space.

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Future Scope

• Ability to store (and search) CDs and audio
  visual aids.
• Web based client interface for the library.
• A text viewer incorporated into the Client
  application.
• Add ratings of the books.

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Thank You