Objective Trustworthiness of Acquaintances in Peer-to-Peer (P2P) Overlay Networks

In fully distributed peer-to-peer (P2P) systems, peers are cooperating with each other by accessing to objects distributed in networks. A peer has to collect correct information on target objects like where target objects exsist and how to manipulate target objects. Some peers may hold obsolete, even incorrect information. Hence, a peer has to find trustworthy acquaintances which hold correct information. There are two types of trustworthiness. The subjective trustworthiness st_st shows how much the peer ps trusts the acquaintance pt through direct communication with pt. The objective trustworthiness ot_st indicates how much other peers trust the acquaintance pt. A peer ps collects subjective trustworthiness on an acquaintance pt from peers and obtains the average value as the objective trustworthiness. In this paper, we discuss protocols to obtain the objective trustworthiness. We evaluate the protocols in terms of how correct objective trustworthiness can be obtained.