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PEER TO PEER (P2P) NETWORK. By: Linda Rockson 11/28/06. Outline:. Definition of Peer-to-Peer (P2P) P2P technologies LimeWire (Latest Technology) How LimeWire works Protocol survey Structured and Unstructured P2P Difference between P2P and server based The future of P2P - PowerPoint PPT Presentation
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PEER TO PEER (P2P) NETWORK
By:
Linda Rockson
11/28/06
Outline:
Definition of Peer-to-Peer (P2P) P2P technologies LimeWire (Latest Technology) How LimeWire works Protocol survey Structured and Unstructured P2P Difference between P2P and server based The future of P2P References and Conclusion
Definition of P2P
A peer-to-peer (P2P) network is one that relies primarily on the resources of the participants in the network rather than on a server
(wikipedia)
P2P Technologies
NapsterGnutellaFreenetKaZaAMorpheusLimeWireBearShare
Napster
Napster (con’t)
Brief HistoryHow Napster works:Central Server (stores location).Peers store filesIs Napster a true P2P?
Gnutella
Gnutella (con’t)
Brief HistoryHow Gnutella works (uses TTL) :No central serverEqual peers - (clients + server
roles)Gnutella - a true P2PAnonymosities
Gnutella (con’t)
LimeWire (Latest Technology)
Fastest File Sharing ProgramGnutella – based application. Open standard software running on
an open protocolAllows file-sharing
for .mp3, .jpg, .tiff, Written in Java.Runs on Windows, Mac, Linux, Sun
How LimeWire works
How LimeWire works (con’t)
Node A1 is first connected to the network.
Pings to Nodes (B and C) to find new nodes on the network.
Pong message(node, IP, port No, No files shared)
Sends a query for files shared by other nodes.
Reply (file(s), size, link speed of the node)
Downloads required file for play/use
Freenet
Brief HistoryHow Freenet worksNo central serverEqual peers - (clients + server roles)Inserting resourcesSearch TerminationAnonymous – secure network
Kazaa
Popular protocols
Fastrack (latest)Morpheus / Bearshare / GnutellaGnutella 2KazaaeDonkeyDC++ (directConnect)Bittorent
FastTrack protocol
Used by KaZaA and MorpheusSupernodes and nodes Scalable Routing Routing RepliesRouting ProblemsPartial Decentralisation
P2P Protocols Problem
Problem: Creates traffic (act server + client)
Solution ET/BWMGR software "sniff out" protocols Controls or block traffic Completely disallows communication Finds protocols irrespective of port used
(80)
Structured and Unstructured P2P
Basis – nodes linkage in the network
Unstructured:Easily constructed: copy existing linksSearches by flooding queriesDisadvantage (unresolved queries)Eg: Napster, Gnutella, KaZaA
Structured P2P
Maintains a Distributed Hash Table (DHT)
Peer responsibility
Searches with hash function
More efficient
Egs: Chord, Tapestry, CAN, Tulip
Advantages of P2P over server based
Inexpensive high scability
Network growth increases resources
No centralized systems – hence cheap
1 program on multiple machines at once
Server: traffic, goes down, resources
Future of Peer-to-Peer
Lack of scalability.
Trust (resources) in the network
Virus control
It must be robust (logout leads to difficult download)
References
users.edinboro.edu/dtuckerwww.google.comwww.howstuffworks.comwww.napster.comwww.kazaa.comwww.gnutella.comwww.limewire.com
Questions / Conclusion
? ? ?? ? ? ?