Abstract  This  paper  proposes  a  new  autonomous  self-organizin g  content-based  node  clustering  peer  to  peer  Information  Retrieval  (P2PIR)  model.  This  model  uses  incrementa l  transitive  document-to-document  similarity  technique  to  build  Local  Equivalence  Classes  (LECes)  of  documents  on  a  sourc e  node.  Locality  Sensitive  Hashing  (LSH)  scheme  is applied  to  map  a  representative  of  each  LEC  into  a  set  of  keys  which   will  be  published  to  hosting  node(s).  Similar  LECes  on  different  nodes  form  Universal  Equivalence  Classes  (UECes),  which  i ndicate  the  connectivity  between  these  nodes.  The  same  LSH  scheme  is  used  to  submit  queries  to  subset  of  nodes  that  most   likely  have  relevant  information.  The  proposed  mod el  has  been  implemented .  The  obtained  results  indicate  efficiency  in  buildi ng  connectivity  between  similar  nodes,  and  correctl y  allocate  and retrieve relevant answers to high percentage of  queries. The system was tested for different network sizes and proved to be  scalable as efficiency downgraded gracefully as the  network size grows exponentially.   

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[26] Zhua Y. and Hub Y., Efficient Semantic Search on DHT Overlays, Parallel Distributed Computing , vol. 67, no. 5, pp. 604-616, 2007. Yaser Al-Lahham received his BS degree from University of Jordan in 1985, the MS degree from Arab Academy Jordan, in 2004, and the PhD degree in computer science from Bradford University, UK in 2009. He is working as an assistant professor in the Department of Computer Science at Zarqa University in Jordan. His research interest includes P2P information retrieval systems, text clustering, and data mining. Mohammad Hassan received his BS degree from Yarmouk University in Jordan in 1987, the MS degree from Univ. of Jordan, in 1996, and the PhD degree in computer information systems from Bradford University, UK in 2003. He is working as an assistant professor in the department of computer science at Zarqa University in Jordan. His research interest includes information retrieval sy stems and database systems.