Example: GNUTELLA Example: GNUTELLA by A though omputer A vu the same pathway. chirehttpconnecti Napster vs GNUTELLA Napster Vs GNUTELLA Napster+ s Gnutella Gives material to its customer in the form of MP3 music files all across the continents. This is the key reason fo Truly decentralized network(pure P2P No single point of failure Share all kinds of Has a provision for redirecting the request, and User friendly and easy to download Napster s Gnutella Server presence slows down or brings services to a halt in No provision for stopping the flood of requests Absence of the server makes user feel unsafe Encounters many bugs in its application, such as and the music industr Working of Various P2P Models Tracing out Other Peers The way an application works matters a lot Essential feature of every P2P-based application A typical P2P-based application can be based Discovering other peers in pure P2P-based model eerstine s dhers dynamically and communicate between Some of the key features every model P2P application should have: sescererins peers en P2P with simple discovery the database of the server stores the information related Querying peers for required content Any query for searching a particular peer is processed by Sharing content /resources with other peer Availability of a large number of peers Single point of failure of se5 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 25 Example: GNUTELLA 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 26 Example: GNUTELLA 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 27 Napster vs GNUTELLA „ Napster + „ Gives material to its customer in the form of MP3 music files all across the continents. This is the key reason for its popularity. „ Provides a protective layer to its user due to the involvement of a server. Fully authenticated data travels on Napster network. „ User friendly and easy to download on your computer „ Napster - „ Server presence slows down or brings services to a halt in case of a technical problem „ Server can easily become the bottleneck „ Works for only MP3 files „ Facing copyright lawyers and the music industry 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 28 Napster vs GNUTELLA „ Gnutella + „ Truly decentralized network (pure P2P) „ No single point of failure „ Share all kinds of files „ Has a provision for redirecting the request, and supports HTTP protocol „ Gnutella - „ No provision for stopping the flood of requests „ Absence of the server makes user feel unsafe „ Encounters many bugs in its application, such as lost packets 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 29 Working of Various P2P Models „ The way an application works matters a lot „ A typical P2P-based application can be based on any of the models „ Some of the key features every model P2P application should have: „ Tracing out other peers „ Querying peers for required content „ Sharing content/resources with other peers 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 30 Tracing out Other Peers „ Essential feature of every P2P-based application „ Discovering other peers in pure P2P-based model „ Peers find others dynamically and communicate between themselves directly „ Affects security „ Discovering peers in P2P with simple discovery server-based model „ The database of the server stores the information related to all registered users „ Any query for searching a particular peer is processed by the server „ Enhanced security „ Availability of a large number of peers „ Single point of failure of server