The Reborn P2P Network Architecture
The concept of Peer-to-Peer networking is not new. It goes
back to the first local networks of computers and, specifically, to the first
interactions of the primitive Internet, long before what is nowadays, dominated
by the WWW.
The concept is the communication between two nodes connected directly without
any kind of mediator.
Peer-to-peer networking is becoming again subject of study
for its application over the Internet. It arose due the popularity of file
sharing applications and communications, pioneered by ICQ and Napster, followed
by the fully decentralized Gnutella network with all its clients like eDonkey,
LimeWire, etc. Finally, a new and more complex scheme was introduced with
the FastTrack architecture over which operates the KazaA application. It is
worth noting that these applications share the same essence, which is the
construction of users communities with the same motivations. For example,
the motivation around ICQ is the instant communication; the motivation of
the Edonkey, Kazaa or Limewire communities, is the sharing of data files and
applications; in the case of Napster or AudioGalaxy the motivation was
exclusive sharing of audio files.
P2P architectures consider that each workstation, personal computer or even a PDA, is a potential data server and processing resource. This consideration is not present in the WEB schema, where a workstation is simply a resource consumer. In the P2P networking over the Internet, the instability of these environment also is considered: a PC can at any time be disconnected without previous warning from the network and therefore the rest of the users should note that the contents that this place offers are not on line. This last fact is not considered in the WEB architecture. The use of DSN assumes that access to a resource will be permanent and it does not consider possibilities of failure. This explains why the result of a query against a search engine gives back inaccessible sites in some cases.
Interesting links
AudioGalaxy, http://www.audiogalaxy.com
eDonkey2000, http://www.edonkey2000.com
Fastrack network, http://www.fasttrack.nu
ICQ, http://www.icq.com
KazaA, http://www.kazaa.com
Limewire, http://www.limewire.com
Napster, http://www.napster.com
Seti@Home project, http://www.setihome.org
The Hyperion Project. University of Toronto, http://www.cs.toronto.edu/db/p2p/The_Hyperion_Project.html
[C2C] Context-to-Context.University of Trento, http://dit.unitn.it/~p2p
Piazza Project. University of Washington, http://data.cs.washington.edu/p2p/piazza
BestPeer Platform, National University of Singapore, http://xena1.ddns.comp.nus.edu.sg/p2p/index.html
Project JXTA Virtual Network, Sun Microsystems, Inc., http://www.jxta.org