Mobile Peer-to-Peer networks are an emerging topic in networking. One of the major usages is the cooperation between peers. The aim of this chapter is to outline cooperation methods and architectures used in these networks. Furthermore, it provides the necessary background on Peer-to-Peer technologies and Mobile Ad Hoc networks together with a comparison that presents the similarities and differences of these two types of networks. Moreover, the major problems the authors face when implementing mobile Peer-to-Peer networks are presented and some proposed solutions are discussed. They then focus on the problem of cooperation in Mobile Peer-to-Peer networks. Furthermore, a number of examples from past research are illustrated and their experimental results are discussed and summarized. Finally, some of the future trends and remaining challenges to be addressed are presented.
Peer-to-Peer (P2P) technology has recently become one of the most frequently mentioned technologies when it comes to file sharing or distributed computation. The term P2P denotes a network of equal peers composing an overlay structure over another network (. The most important aspect of P2P is that these peers communicate using certain protocols without the need of a central coordinator.
This type of communication has been mainly used in file sharing applications, but other uses such as distributed computation, voice over P2P and P2P television are also possible.
Most of these protocols require a hard-wired infrastructure with a standard topology such as the Internet. On the other hand, Mobile Ad Hoc Networks (MANETs) do not have such an infrastructure and their topology is constantly changing. This leads us to the challenge of finding new protocols and creating new techniques for implementing P2P networks over MANETs.
By using these protocols and techniques, we can introduce new services or improve existing ones. There are features of MANETs such as context awareness and resource availability, which do not exist in classic wired networks and can help improve P2P networks (Gold & Mascolo, 2001). New algorithms have been proposed to improve the performance of various aspects such as routing. Furthermore, new services have been introduced, e.g. collaboration frameworks (Kortuem et al., 2001), which are based on the social encounters in Mobile P2P networks.
The remainder of the chapter is organized as follows. The Background section presents a short introduction to P2P and MANETs and how P2P technology works over MANETs. The Cooperation in Mobile Peer-to-Peer Networks section describes current methods for cooperation over standard and Mobile P2P networks. Examples of such networks are also given in addition to a discussion about their potential usage. The Future Trends section discusses a number of open research issues and identifies some areas for future research. Finally, the chapter concludes with a summary of the materials presented.