ABSTRACT
The extreme decentralization, dynamism, and self-organization of a number of emerging environments, including teamwork, pure peer-to-peer (P2P), andmobile ad hoc networks (MANETs), where nodes are involved in the process of sharing and collaboration without relying on central authorities, enforce the overall cooperation to play an essential role. Particularly, ad hoc networks rely upon the cooperation among individual nodes to carry out essential tasks such as packet forwarding. P2P file sharing systems face a similar situation. This collaboration-based nature of the communication
layers imposes a number of challenges in the provision of other services, especially concerning security. In fact, most of the difficulties found to apply classic security solutions are just related to the inherent lack of central authorities, such as public key infrastructures (PKIs), and new proposals have to deal with avoiding such a centralization by exploring alternative paradigms which, in turn, require cooperation among peers. In this chapter, we elaborate on the concept of cooperation-based security services, such as authentication and access control, and is concluded by pointing out some open research issues and emerging trends in this research area.
