文档介绍：Peer-to-Peer
Networking:
The Past and Future of the

Jeff Doyle
IPv6 Solutions Manager
jeff@
1
What is Peer-to-Peer (P2P)?
P2P: The sharing puter resources and services
by direct exchange between systems.*
* P2P Working Group
…this is one of the characteristics of the early
2
What Happened?
• The has evolved into a “Services in the
Middle” model
• Information and services flow primarily toward the
user
• Contributing factors:
• Commercial interests
Consumer Consumer
• Legacy of low-powered PCs
• NAT work SERVICES
transparency Consumer Consumer
Consumer Consumer
Consumer
3
The Lessons of Napster
• Napster led the way
• User driven
• Intelligent application of client/server
and peer-to-peer
• Simple model made unnecessarily
complex by dynamic IP issues
4
The Lessons of Napster
• But peer-to-peer is about more than sharing
music files (legally or otherwise)
• Peer-to-peer might re-shape the way we do
business
• P2P currently seen as a threat to entertainment
industry and other producers of copyrighted material
• A new business model is required
5
New P2P Applications
• Content sharing
• Napster was a wake-up call
• Kazaa
• Morpheus, , Grokster,
Gnutella, many more…
• Distributed data processing
• ******@home
• ******@home
• Popular Power
• United Devices
Distributed applications
• Black-hat hackers already appreciate this (DDoS)
6
******@home:
The Power of Distributed Processing
• 1 work unit = trillion floating-point operations
• 700,000 work units performed per day = 20 TFLOPS
•~2X speed of fastest current puter
•< 1% the cost of the fastest current puter
7
The New P2P Paradigm
• P2P applications can be:
• Fully P2P
• P2P and client-server
• Fully server based
• If P2P can be fully server based, what does P2P really mean?
P2P: A group of nodes actively
participating in puting process
• Peer machines can be both clients and servers
• U