The new territory of mobile agreement

The fault-tolerance is an important research topic in the study of distributed systems. To cope with the influence from faulty processors, reaching a common agreement at the presence of faults before performing some special tasks is essential. Therefore, the Byzantine Agreement (BA) problem has drawn more and more of the researchers' attention as they explore deeper and deeper into the world of distributed systems. Traditionally, the BA problem is solved in the fully connected network or in the broadcast network. However, the technology of network continues to grow at high-speed, it promotes the wireless and mobile computer to become increasingly popular. It can also provide support for mobile computing. This environment encourages distributed system design and practice to support mobile processors greatly. The mobile network is different from the fully connected network or broadcast network; processors in mobile environment have high mobility. The processors may immigrate into or move away from the network at any time. How the processors reach an agreement in the mobile network must also be concerned deeply. In this paper, BA problem is reexamined under the mobile network. The proposed protocol Byzantine Agreement under Mobile Network (BAMN) uses the minimum number of message exchanges to reach an agreement while tolerating the maximum number of faulty processors in a mobile environment. It makes all the healthy processors reach a common value to keep the system from the influences of processor failures. (C) 2004 Elsevier B.V. All rights reserved.