Chapter 7: P2P Application Chapter 7: P2P Application development development Chapter goal: Chapter goal P2P applicat P2P application model P2P applicati P2P application design P2P examp P2P example What is Peer-To-Peer?(1/3 What is Peer-To-Peer?(2/3) P2P is a class of applications that P2P computing is etc)-available at the edges of the ine CPu Takes advante The sharing of computer resources and ccessing these decentralized rvices by direct exchange between esources means opera editable Peer-to-peer computing takes advantage DNS system and have significant or total of existing computing power and autonomy from central servers. networking connectivity, allowing collective power to benefit the entire enterprise. What is Peer-To-Peer? (3/3) A Brief History of P2P P2P computing is distributed a P2P is not a new technology computing with the following desirable Resource Sharing As result o de pplrcasied isemortd e aring files nare resources Dual client/server role Decentralization/Autonomy became increasingly powerful Scalabil Robustness/Self-Organization is still P2P 1999-2000, Napster shows the true potential of Pa1 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 1 Chapter 7: P2P Application development Chapter goal: „ P2P application model „ P2P application design „ P2P example 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 2 Chapter 7: P2P Application development Chapter goal: „ P2P application model „ P2P application design „ P2P example 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 3 What is Peer-To-Peer? (1/3) „ P2P is a class of applications that: „ Takes advantage of resources – (storage, CPU, etc,..) – available at the edges of the Internet. „ Because accessing these decentralized resources means operating in an environment of unstable connectivity and unpredictable IP addresses, P2P nodes must operate outside the DNS system and have significant or total autonomy from central servers. 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 4 What is Peer-To-Peer? (2/3) „ P2P computing is: „ The sharing of computer resources and services by direct exchange between systems. „ Peer-to-peer computing takes advantage of existing computing power and networking connectivity, allowing economical clients to leverage their collective power to benefit the entire enterprise. 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 5 What is Peer-To-Peer? (3/3) „ P2P computing is distributed computing with the following desirable properties: „ Resource Sharing „ Dual client/server role „ Decentralization/Autonomy „ Scalability „ Robustness/Self-Organization 哈工大计算机学院 李全龙 Network Application Development P2P Application Development 6 A Brief History of P2P „ P2P is not a new technology „ It has existed since the Internet was taking form in the 1970s „ Recent changes in technology and the improved computing capability of desktops have brought about P2P’s revival on a larger scale „ P2P model-based application is confined to sharing files „ As a result of the increased demand for Web-base services, users felt the need to control, exchange, and share resources directly „ Meanwhile, in the late 1990s, PCs became increasingly powerful in terms of speed and processing power „ Software developers realized that they could put server software on individual PCs and initiate a direct two-way data flow between two peers „ Led to the revival of P2P „ Interestingly, the IP routing infrastructure is still P2P „ 1999-2000, Napster shows the true potential of P2P