A new IRTF research group, P2PRG (Peer-to-Peer Research Group), has begun, with the appended charter. Use p2prg-request@ietf.org to subscribe to the mailing list. - Vern Paxson (IRTF chair) -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Charter ------- Peer-to-Peer (P2P) is a way of structuring distributed applications such that the individual nodes have symmetric roles. Rather than being divided into clients and servers each with quite distinct roles (such as Web clients vs. Web servers), in P2P applications a node may act as both a client and a server. P2P systems are in general deployable in an ad-hoc fashion, without requiring centralized management or control. They can be highly autonomous, and can lend themselves to anonymity. Some historical examples of P2P systems are USENET servers, built on top of NNTP, and inter-domain routing, built on top of BGP. A key concept for P2P systems is to permit any two peers to communicate with one another in such a way that either ought to be able to initiate the contact. As such, P2P is a powerful tool for organizing cooperative communities - both in the research and commercial domains - with common goals. However, in practice, we find that the research and commercial worlds are driven by different needs. The former often focusses on developing generalized building blocks that can then be composed to realize P2P systems with quantifiable properties. These building blocks sometimes arise out of analysis of the deficiencies of existing P2P systems, attempting to overcome discovered shortcomings in areas such as peer-node organization, content caching and distribution, lookup, search, discovery, routing, security and trust. The commercial P2P world, on the other hand, is driven by the concerns of time-to-market and viable business models. Many commercial systems have little concern for the research issues mentioned above, while the short-term concerns of commercial entities are often not within the purview of academic research. Such discontinuites in perspective have led to a rift between the two communities, bridging which will be of significant short- and long-term benefit. The P2P Research Group attempts to serve as such a bridge. First, the group offers a forum for researchers to explore a broad range of fundamental P2P issues such as: peer-node identity, naming, configuration and capabilities; P2P network organization and scope; resource discovery, content lookup, search and distribution; request routing and operation in the presence of mobility; adaptation to expected peer-node instability; monitoring of P2P operations; security of P2P systems involving reputation-based trust for ad-hoc systems or more centralized, CA-like approaches; etc. In addition, as commercial P2P deployment on the Internet has raced ahead of research and standards, issues as basic as interoperable, scalable, P2P communication protocols have been set aside. There is no foundation upon which one can build a unified, P2P network on the Internet: today's P2P protocols create disjoint islands of isolated Internet nodes. To this end, the research group also emphasizes the following near-term goals: classifying the P2P problem space (both currently, and as it evolves) into those problems for which there are existing solutions and those for which solutions require longer-term development; developing descriptive model(s) of peer-node organization whose interpretation can be applied to these solutions; articulating the scope as to what sort of P2P applications the models encompass and what sort they do not; understanding the unique security-related problems and opportunities P2P systems pose; exploring interfaces to IETF protocols to realize the models; and offering input to the IETF as a starting place for possible groups standardizing new protocols that are useful in building P2P applications.
