Still the best overview I know of

It's five years old by now, which is a long time in this industry, but the book remains relevant by virtue of the solid writing and lack of fluff that we expect from O'Reilly, and by the third section's excellent in-depth coverage of fundamental issues: Performance, Trust, Accountability, Reputation, Security. Each of these has a lot of valuable information, references and ideas.

Particularly valuable to me were the discussions of:
- Analyzing and optimizing peer connection graphs
- How Groove uses cryptography to protect and authenticate data
- Using token economies and "nonfungible micropayments" to avoid denial-of-service attacks
- How trust relationships can be tracked

The coverage of specific technologies hasn't aged quite as well. There's too much on things that either never went anywhere (Red Rover?) or are extremely primitive by today's standards (Gnutella), while very important more recent ones like BitTorrent and Kademlia are understandably missing.

Still, as I said, I don't think there's a better book out there. I've bought others and been disappointed by their superficiality, even the "academic" books. Buy this one, and then be prepared to do some intensive web searching/surfing for research papers to catch up on later developments like Distributed Hash Tables, BitTorrent, Kademlia, Chord, Pastry, Coral, JXTA, PNRP, Bonjour...

Other Reviews

• This book changed my life
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