Peer-to-Peer: Harnessing the Power of Disruptive Technologies

by Andy Oram (Editor)

Overview

The term "peer-to-peer" has come to be applied to networks that expect end users to contribute their own files, computing time, or other resources to some shared project. Even more interesting than the systems' technical underpinnings are their socially disruptive potential: in various ways they return content, choice, and control to ordinary users.While this book is mostly about the technical promise of peer-to-peer, we also talk about its exciting social promise. Communities have been forming on the Internet for a long time, but they have been limited by the flat interactive qualities of email and Network newsgroups. People can exchange recommendations and ideas over these media, but have great difficulty commenting on each other's postings, structuring information, performing searches, or creating summaries. If tools provided ways to organize information intelligently, and if each person could serve up his or her own data and retrieve others' data, the possibilities for collaboration would take off. Peer-to-peer technologies along with metadata could enhance almost any group of people who share an interest—technical, cultural, political, medical, you name it.This book presents the goals that drive the developers of the best-known peer-to-peer systems, the problems they've faced, and the technical solutions they've found. Learn here the essentials of peer-to-peer from leaders of the field:

• Nelson Minar and Marc HedlundPopular Power, on a history of peer-to-peer
• Clay Shirky of acceleratorgroup, on where peer-to-peer is likely to be headed
• Tim O'Reilly of O'Reilly & Associates, on redefining the public's perceptions
• Dan Bricklin, cocreator of Visicalc, on harvesting information from end-users
• David Anderson of SETI@home, on how SETI@Home created the world's largest computer
• Jeremie Miller of Jabber, on the Internet as a collection of conversations
• Gene Kan of Gnutella and GoneSilent.com, on lessons from Gnutella for peer-to-peer technologies
• Adam Langley of Freenet, on Freenet's present and upcoming architecture
• Alan Brown of Red Rover, on a deliberately low-tech content distribution system
• Marc Waldman, Lorrie Cranor, and Avi Rubin of AT&T Labs, on the Publius project and trust in distributed systems
• Roger Dingledine, Michael J. Freedman, andDavid Molnar of Free Haven, on resource allocation and accountability in distributed systems
• Rael Dornfest of O'Reilly Network and Dan Brickley of ILRT/RDF Web, on metadata
• Theodore Hong of Freenet, on performance
• Richard Lethin of Reputation Technologies, on how reputation can be built online
• Jon Udell ofBYTE and Nimisha Asthagiri andWalter Tuvell of Groove Networks, on security
• Brandon Wiley of Freenet, on gateways between peer-to-peer systems

You'll find information on the latest and greatest systems as well as upcoming efforts in this book.

Product Details

ISBN-13:	9780596001100
Publisher:	O'Reilly Media, Incorporated
Publication date:	03/28/2001
Edition description:	1 ED
Pages:	448
Product dimensions:	6.00(w) x 9.00(h) x 1.17(d)

About the Author

Andy Oram is an editor at O'Reilly & Associates, specializing in books on Linux and programming. Most recently, he edited Peer-to-Peer: Harnessing the Power of Disruptive Technologies.

Table of Contents

Preface; Some context and a definition; How this book came into being; Contents of this book; Peer-to-peer web site; We’d like to hear from you; Context and Overview; Chapter 1: A Network of Peers: Peer-to-Peer Models Through the History of the Internet; 1.1 A revisionist history of peer-to-peer (1969-1995); 1.2 The network model of the Internet explosion (1995-1999); 1.3 Observations on the current crop of peer-to-peer applications (2000); 1.4 Peer-to-peer prescriptions (2001-?); 1.5 Conclusions; Chapter 2: Listening to Napster; 2.1 Resource-centric addressing for unstable environments; 2.2 Follow the users; 2.3 Where’s the content?; 2.4 Nothing succeeds like address, or, DNS isn’t the only game in town; 2.5 An economic rather than legal challenge; 2.6 Peer-to-peer architecture and second-class status; Chapter 3: Remaking the Peer-to-Peer Meme; 3.1 From business models to meme maps; Chapter 4: The Cornucopia of the Commons; 4.1 Ways to fill shared databases; Projects; Chapter 5: SETI@home; 5.1 Radio SETI; 5.2 How SETI@home works; 5.3 Trials and tribulations; 5.4 Human factors; 5.5 The world’s most powerful computer; 5.6 The peer-to-peer paradigm; Chapter 6: Jabber: Conversational Technologies; 6.1 Conversations and peers; 6.2 Evolving toward the ideal; 6.3 Jabber is created; 6.4 Conclusion; Chapter 7: Mixmaster Remailers; 7.1 A simple example of remailers; 7.2 Onion routing; 7.3 How Type 2 remailers differ from Type 1 remailers; 7.4 General discussion; Chapter 8: Gnutella; 8.1 Gnutella in a gnutshell; 8.2 A brief history; 8.3 What makes Gnutella different?; 8.4 Gnutella’s communication system; 8.5 Organizing Gnutella; 8.6 Gnutella’s analogues; 8.7 Gnutella’s traffic problems; 8.8 The policy debates; 8.9 Gnutella’s effects; Chapter 9: Freenet; 9.1 Requests; 9.2 Keys; 9.3 Conclusions; Chapter 10: Red Rover; 10.1 Architecture; 10.2 Client life cycle; 10.3 Putting low-tech “weaknesses” into perspective; 10.4 Acknowledgments; Chapter 11: Publius; 11.1 Why censorship-resistant anonymous publishing?; 11.2 System architecture; 11.3 Cryptography fundamentals; 11.4 Publius operations; 11.5 Publius implementation; 11.6 Publius MIME type; 11.7 Publius in a nutshell; Chapter 12: Free Haven; 12.1 Privacy in data-sharing systems; 12.2 Anonymity for anonymous storage; 12.3 The design of Free Haven; 12.4 Attacks on Free Haven; 12.5 An analysis of anonymity; 12.6 Future work; 12.7 Conclusion; 12.8 Acknowledgments; Technical Topics; Chapter 13: Metadata; 13.1 Data about data; 13.2 Metadata lessons from the Web; 13.3 Resources and relationships: A historical overview; 13.4 Conclusion; Chapter 14: Performance; 14.1 A note on terminology; 14.2 Why performance matters; 14.3 Bandwidth barriers; 14.4 It’s a small, small world; 14.5 Case study 1: Freenet; 14.6 Case study 2: Gnutella; 14.7 Conclusions; 14.8 Acknowledgments; Chapter 15: Trust; 15.1 Trust in real life, and its lessons for computer networks; 15.2 Trusting downloaded software; 15.3 Trust in censorship-resistant publishing systems; 15.4 Third-party trust issues in Publius; 15.5 Trust in other systems; 15.6 Trust and search engines; 15.7 Conclusions; Chapter 16: Accountability; 16.1 The difficulty of accountability; 16.2 Common methods for dealing with flooding and DoS attacks; 16.3 Micropayment schemes; 16.4 Reputations; 16.5 A case study: Accountability in Free Haven; 16.6 Conclusion; 16.7 Acknowledgments; Chapter 17: Reputation; 17.1 Examples of using the Reputation Server; 17.2 Reputation domains, entities, and multidimensional reputations; 17.3 Identity as an element of reputation; 17.4 Interface to the marketplace; 17.5 Scoring system; 17.6 Reputation metrics; 17.7 Credibility; 17.8 Interdomain sharing; 17.9 Bootstrapping; 17.10 Long-term vision; 17.11 Central Reputation Server versus distributed Reputation Servers; 17.12 Summary; Chapter 18: Security; 18.1 Groove versus email; 18.2 Why secure email is a failure; 18.3 The solution: A Groove shared space; 18.4 Security characteristics of a shared space; 18.5 Mutually-trusting shared spaces; 18.6 Mutually-suspicious shared spaces; 18.7 Shared space formation and trusted authentication; 18.8 Inviting people into shared spaces; 18.9 The New-Member-Added delta message; 18.10 Key versioning and key dependencies; 18.11 Central control and local autonomy; 18.12 Practical security for real-world collaboration; 18.13 Taxonomy of Groove keys; Chapter 19: Interoperability Through Gateways; 19.1 Why unification?; 19.2 One network with a thousand faces; 19.3 Well-known networks and their roles; 19.4 Problems creating gateways; 19.5 Gateway implementation; 19.6 Existing projects; 19.7 Conclusion; 19.8 Acknowledgments; Chapter 20: Afterword; 20.1 Precedents and parries; 20.2 Who gets to innovate?; 20.3 A clean sweep?; Directory of Peer-to-Peer Projects; Contributors;

Editorial Reviews

The Barnes & Noble Review
Peer-to-peer computing over the Internet. Just a fancy way of saying "steal free MP3s with Napster or Gnutella"? Think again.

Tim O'Reilly, publisher and proprietor of O'Reilly & Associates, brought together leading players throughout the nascent P2P market space last September for a wide-ranging discussion of P2P's remarkable potential. The rough consensus amongst the new P2P movers and shakers: think of P2P as "an operating system for the Internet."

Operating systems deliver services, and P2P's go far beyond file sharing. For example, P2P may enable next-generation instant messaging and presence management. It may make possible entirely new forms of collaboration, starting with ad-hoc peer-to-peer software development workgroups.

P2P can leverage distributed computation, where millions of PCs -- whose processing cycles are mostly wasted -- share tasks too large for any individual system to perform. (Proof of concept: SETI@home, wherein over 2.5 million PCs worldwide have contributed data analysis to the search for extraterrestrial intelligence).

P2P can lead to revolutionary new Web services, new ways to hyperlink, and a whole new view of the Web, where millions of people aren't just passively consuming content and services: they're providing them as well.

One outgrowth of last Fall's P2P summit is a remarkable book: Peer-to-Peer: Harnessing the Disruptive Potential of Collaborative Networking. In this book, P2P's leading practitioners offer in-depth, technically significant discussions of nearly all the key issues they face in transforming P2P from hope to reality. O'Reilly's worked hard to find people who have something important to say and framed the book with its own thoughtful commentary. The result is nothing less than a first sketch of the next Internet revolution as it takes shape.

Section I of this book offers much-needed perspective. Nelson Minar and Marc Hedlund point out that the Internet began as a peer-to-peer operation (all the original ARPANET hosts were equal peers), and that early applications like Usenet implemented decentralized control mechanisms that have echoes in today's newest thinking about P2P.

In a brilliant essay entitled Listening to Napster, Clay Shirky starts by precisely defining P2P as "a class of applications that takes advantage of resources -- storage, cycles, content, human presence -- available at the edge of the Internet." Shirky outlines the important technical implications that flow from this definition; then informs P2P with the common-sense lessons we've learned about the Internet and other technologies: "Users reward simplicity," "It's the applications, stupid," and "Decentralization is a tool, not a goal."

Finally, Dan Bricklin, inventor of VisiCalc -- the first spreadsheet and the classic PC killer app -- makes the case that Napster "harnesses the disruptive potential of personal selfishness." The more downloads, the more resources are available to everyone: "...increasing the value of the database, by adding more information, is a natural by-product of each person using the tool for his or her own benefit." (Bricklin has his doubters, who wonder how well P2P applications will scale when 50 people take resources for each one who provides them.)

Part II of this book focuses on several real-world P2P projects. In addition to SETI@home, you'll find coverage of Jabber, an open source, XML-based instant messaging system that lets you chat with folks on AOL IM, ICQ, MSN, Yahoo, and IRC, all from the same client software. There are chapters on P2P applications intended to protect individual email privacy (Mixmaster), resist censorship (Red Rover), allow for anonymous uploads and downloads (Freenet and Free Haven), and make it possible to publish anonymously, like James Madison in The Federalist Papers (Publius).

Part III focuses on the technology of P2P: the crucial role of metadata; performance optimization; building networks that don't rely on trust; making resource hogs accountable; and providing security and interoperability. There's much work to be done, but you'll be surprised how much thought and sweat have gone into these issues.

It remains to be seen whether the P2P revolution will meet its potential. But if it does, people will view this book as the manifesto that made it all come together.(Bill Camarda)

Bill Camarda is a consultant and writer with nearly 20 years' experience in helping technology companies deploy and market advanced software, computing, and networking products and services. His 15 books include Special Edition Using Word 2000 and Upgrading & Fixing Networks For Dummies®, Second Edition.

bn.com

Software projects like Napster and Freenet have challenged traditional approaches to content distribution with their use of peer-to-peer file-sharing technologies. In this book, key peer-to-peer pioneers offer insight on how the technology has evolved and where it's going. They draw on their experiences in business and technology to explore problems and solutions and contemplate the future of computer networking. Issues discussed include accountability, security, metadata, performance, and interoperability. Oram writes and edits books on programming and networking. Annotation c. Book News, Inc., Portland, OR (booknews.com)

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