Why P2P
From P2P Wiki
P2P technologies are just beginning to change the way people and computers interact in the Internet. P2P applications like file sharing, distributed computing or VoIP have already atracted millions of users. Furthermore, P2P has a brilliant future in settings like P2P TV, Distributed Storage, Grid systems, Mobile devices, Internet Infrastructures and Social Networks among others.
P2P Systems are popular because of the many benefits that they offer: adaptation, self-organization, fault tolerance and massively distribution and replication of large amount of resources. On the one hand, Collaborative P2P systems aim to benefit from the huge amount of unused resources of desktop computers (content, data storage, cpu, bandwidth) to create the next generation of Internet Infrastructures. On the other hand, P2P is particularly challenging for developing collaborative information systems. In this line, P2P can be used to create social networks and communities, to discover users and information, to aggregate community contents or even as a communication medium for large groups.
Quoting Pablo Rodriguez's BLOG about "Learn from P2P Systems":
One thing that it is clear to me is that there are several lessons to be learnt from P2P systems. In fact, I would argue that most of the innovations in networking space during the last years have come from P2P systems (new routing algorithms, swarming protocols, NAT traversal, overlay naming, etc).
Why? well, I guess because people got tired of waiting for THE network to support IP multicast, anycasting, content-based naming, full host reachability, etc. Users got frustrated to hear that to test their ideas they had to change all routers in the world, build a new infrastructure overlay, or yet, convince all ISPs in the Internet. Instead, users realized the power of deploying new services with a simple piece of software that turned their personal computers into network elements. And voila, there you have it, some of the most successful and scalable systems ever deployed, Skype, BitTorrent, and more to come.
The beauty of P2P systems is that one can deploy hugely scalable services completely bypassing ISPs and without the need for end2end multicast, in a similar way that the Internet created a network that could route packets without having to go through the centralized control of phone operators.
