Byzantine Agreement & Fault Diagnosis Agreement in Dynamic Ad-Hoc Environment

Since wireless communication and mobile computing are becomingmore and more ubiquitous, the reliability and fault tolerance of the Mobile Ad-hoc Network (MANET) has become an important topic. In order to provide a reliable environment, a mechanism that allows a set of nodes to reach a common agreement, even in the presence of faulty nodes, is needed. Therefore, the Byzantine Agreement (BA) problem has drawn attention of more researchers. Traditionally, the BA problem was focused on wired networks. We know that the physical topology of a wired network is static, but the physical topology of an MANET is dynamic. Thus, previous BA protocols are not applicable in an MANET. In this paper, a new protocol is proposed to solve the BA problem with malicious faulty components in dynamic MANET. Furthermore, we also propose a new Fault Diagnosis Agreement (FDA) protocol to detect/locate faulty components to provide a highly reliable environment. From the performance perspective, the proposed protocols use the minimum number of message exchanges and can tolerate/detect/locate the maximum number of faulty nodes allowed in the dynamic network.