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Performance Analysis of an ISP-Based Distributed Sloppy Hash Table

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Performance Analysis of an ISP-Based Distributed Sloppy Hash Table Master’s Thesis Electrical Engineering Thesis no:MEE10:110 March 2011 Performance Analysis of an ISP-based Distributed Sloppy Hash Table MD. WAHID MURAD ODION EHIMIAGHE School of Engineering Blekinge Institute of Technology 371 79 Karlskrona Sweden This thesis is submitted to the School of Engineering at Blekinge Institute of Technology in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering. This thesis is equivalent to 20 weeks of full time studies. Contact Information: MD. WAHID MURAD Email: [email protected] ODION EHIMIAGHE Email: [email protected] Advisor: Karel De Vogeleer School of Computing Blekinge Institute of Technology 371 79, Karlskrona, Sweden Email: [email protected] University Examiner: Patrik Arlos School of Computing Blekinge Institute of Technology 371 79, Karlskrona, Sweden Email: [email protected] School of Engineering Internet : www.bth.se/com Blekinge Institute of Technology Phone : +46 455 38 50 00 371 79 Karlskrona Fax : +46 455 38 50 57 Sweden ii ABSTRACT Distributed Hash Table (DHT) systems are the basics for routing protocols in peer- to-peer network, suitable for flat design (non-hierarchical systems) ensuring evenly distributed file storage. But a well structured and hierarchical system providing for scalability, fault tolerance and to cater adequately for web cashing and multicast resource control in Internet applications in mobile environment is the use of distributed sloppy hash table (DSHT). In our work we will be working on how a well structured overlay application that will perform better in terms of scalability, lookup time and ease of use. We will focus on the application of real time usage with the incorporation of ISP (internet service provider) based partitioning for DSHTs. The sloppy hash DHT is employed to take advantageous use of low round trip times. The ISP bash DSHT yields some additional benefits to regular DHTs. These benefits include the use of pointers to reference keys in particular layers, thereby avoiding data replication at nodes for bandwidth utilization. Also, effective use of spillover in concentric rings is employed for load balancing and the phenomenon of distance optimization by the introduction of geographical proximity. ACKNOWLEDGEMENTS In the name of Allah (God), the most Beneficent and the most Merciful First of all we start by thanking God for assisting and guiding us in this work. We thank him for giving us the confidence and patience to finish thesis work. We would like to thank our Supervisor, for his continuous guidance and advice in order for us to be able to finish our entire thesis work successfully while working. He has been a sincere mentor to us, doing a quality research from the very beginning. He kept us focused on our thesis and helped us improve the quality of our thesis by giving valuable feedback. We also would like to thank our examiner; who is in charge for encouraging us to do a quality thesis as well as keeping us actively involved with our thesis work to ensure a timely finish. An attempt of this nature required a lot of support and we would like to proudly mention that our family kept their support for us. We have to thank our parents, friends and families for being tremendously supportive while we were working on this thesis. ii CONTENTS ABSTRACT ........................................................................................................................................................... I ACKNOWLEDGEMENTS ..............................................................................................................................II CONTENTS ........................................................................................................................................................III LIST OF FIGURE ............................................................................................................................................. VI LIST OF TABLE ............................................................................................................................................. VII 1 CHAPTER: INTRODUCTION..............................................................................................................1 1.1 INTRODUCTION.....................................................................................................................................1 1.2 MOTIVATION ........................................................................................................................................2 1.3 AIM AND OBJECTIVE ...........................................................................................................................3 1.4 RESEARCH QUESTIONS........................................................................................................................4 1.5 RESEARCH METHODOLOGY ...............................................................................................................4 2 CHAPTER: BACKGROUND.................................................................................................................5 2.1 PEER-TO-PEER ......................................................................................................................................5 2.1.1 Network Topologies.......................................................................................................................6 2.1.2 Centralized systems........................................................................................................................6 2.1.3 Decentralized systems ...................................................................................................................7 2.1.4 Unstructured Network ...................................................................................................................8 2.1.5 Ring system .....................................................................................................................................9 2.1.6 Structured network .........................................................................................................................9 2.1.7 DHT (Distributed Hash Table).....................................................................................................9 2.1.8 System maintenance of DHT......................................................................................................10 2.1.9 Iterative Routing ...........................................................................................................................11 2.1.10 Recursive Routing ...................................................................................................................11 2.1.11 Data storage system in DHT..................................................................................................12 2.1.12 Super peer or hybrid systems (hierarchical routing scheme) ...........................................12 2.1.13 Hierarchical routing in internet .............................................................................................13 2.1.14 Lookup services .......................................................................................................................13 2.1.15 Hierarchical Lookup Mechanism..........................................................................................14 2.1.16 Advantages of Hierarchical Architecture ............................................................................14 2.2 CHORD .................................................................................................................................................15 2.3 CORAL .................................................................................................................................................16 2.3.1 Coral Indexing Abstraction.........................................................................................................16 2.4 DIFFERENCE BETWEEN ST RUCTURED AND UNSTRUCTURED P2P SYSTEM.................................17 2.5 ISP........................................................................................................................................................18 2.6 MOBILITY MANAGEMENT ................................................................................................................18 3 CHAPTER: RELATED WORK ..........................................................................................................21 3.1 CHORD .................................................................................................................................................21 3.1.1 Routing ...........................................................................................................................................22 3.1.2 Joining the Chord DHT ...............................................................................................................23 3.1.3 Maintaining correct routing information ..................................................................................24 3.1.4 Replication .....................................................................................................................................25 3.1.5 Leaving the Chord DHT..............................................................................................................25 3.2 KADEMLIA ..........................................................................................................................................26 3.2.1 Routing of Kademlia....................................................................................................................27
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