Evaluating scalability Peer-to-Peer File Sharing Networks of Sayantan Mitra Vibhor Goyal

Peer – to – Peer Networks P2P networks are built to share files amongst various peers. A central server serves as an index. The decision on which peer will serve the file transfer to the requesting peer is done by the central server. To ensure the correctness of file transfer, Hash checking mechanism is provided by the server. 2

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P2P Bandwidth Share 4

P2P Framework Join How do I begin participating? Publish How do I advertize myself? Search How do I find a file? Fetch How do I retrieve a file? 5

Centralized System Join On startup, client contacts central server. Publish Reports list of files to central server. Search query the server => return node(s) that store the requested file. 6

Design 7

Why Scaling is a problem in P2P??? Millions of clients=> server and network meltdown!! 8

Scalability Analysis Dropped Packets. Handling of File Requests with increase in simultaneous access demand. SHA-1 mismatch. Bandwidth usage. Latency. Network delay. 9

P2P characteristics for evaluation Datasets follow zipf’s law:  Bursty.  Random Skewed.  Distributed. File Transfer follows principle of GNUtella. Sliding window Protocol. 10

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