Adaptive voting algorithms for the reliable dissemination of data in fault-prone distributed environments
Kaliappa Ravindran, Kevin A. Kwiat, Patrick Hurley · International Journal of Business Intelligence and Data Mining · 2008
Data collection in a distributed embedded system requires dealing with failures: data corruptions by malicious devices and arbitrary message delays/loss in the network. Replication of data collection devices deals with such failures by voting among the replica devices to move a correct data to the end-user. Here, a data voted upon can be large-sized and/or take a long time to be compiled (e.g., terrain surveillance images). The goal of our paper is to engineer the voting protocols for good performance while meeting the reliability requirements of data delivery in a high assurance setting. Two metrics quantify the effectiveness of voting protocols: Data Transfer Efficiency (DTE) and Time-To-Complete (TTC) data delivery. DTE captures the network bandwidth wasted and/or the energy drain in wireless-connected devices; whereas, TTC captures the degradation in user-level Quality of Service (QoS) due to delayed/missed data deliveries. Given the distributed nature of voting, our protocol-level optimisations to improve DTE and TTC reduce the movement of user-level data over network, the number of control messages generated, and the latency in effecting a data delivery. The paper describes these optimisations, and reports experimental results from a prototype voting system. The paper also describes a case study of voting deployed in web service access to information repositories.