Design of Avionics Network Architecture under a Reliability Constraint

Reliability is an important aspect of operatingsafety-critical applications of networked systems, such as inavionics. In order to ensure sufficient reliability, one approachis to apply redundancy. However, redundancy may be costlyif the degree of redundancy is too high. This paper proposesan optimization-based framework for guaranteeing the desiredreliability of any graph-based networked system. It focuses onintegrated modular avionics architecture, based on the use ofminimally redundant components. This framework consists oftwo steps. The first is to compute the minimum number ofcomponents within the architecture, using a geometric program.The second is to determine the topology with the minimal numberof connections between these components, using a signomialprogram. Finally, the method is illustrated on a small examplenetwork and a larger network of the A350 avionics architecture.

Finite-Level Quantized Consensus of Multi-agent Networked Systems

This paper is concerned with the analysis of consensus multi-agent networked system. Adopted in the analysis is the finite-level logarithmic quantizer, for the transmission of the networked-agents state. Two protocols are utilised in the analysed multi-agent networked system: the consensus protocol, which is determined from the outputs and states of a set of encoder-decoder pair that is employed in the system, and convergence rate protocol that is precisely characterized via the use of a dynamic scaling factor. With information exchange among neighbouring agents, the asymptotic consensus can be reached. The proof of protocols is based on proper selection of parameters of the logarithmic quantizer chosen for the connected network. As a demonstration of the validity of the protocols, a four-agent networked system is used. It is shown that an undirected network exchange of information via a communication channel that is equipped with a set of encoder and decoder can lead to attainment of estimates of neighbour state protocol for the networked system. Furthermore, desired asymptotic convergence can be reached through appropriate choice of parameters of the logarithmic quantizer.

Protocol State Machine Reverse Engineering with a Teaching-Learning Approach

In this work, we propose a novel solution to the problem of inferring the state machine of an unknown protocol. We extend and improve prior results on inferring Mealy machines, and present a new algorithm that accesses and interacts with a networked system that runs the unknown protocol in order to infer the Mealy machine representing the protocol's state machine. To demonstrate the viability of our approach, we provide an implementation and illustrate the operation of our algorithm on a simple example protocol, as well as on two real-world protocols, Modbus and MQTT.

"Die-Hard Supporters"

The success of the maverick politician Rodrigo Duterte in the 2016 election is cited as a result of the weaponization of social media—whereby professional, tech-savvy strategists mobilized public opinion through a networked system of disinformation. Yet, there is evidence of grassroots campaign support that emerged via online platforms. Those who have mobilized include Overseas Filipino Workers (OFWs), who have used Facebook groups to rally in support of Duterte. This research looks at the activities of two OFW Facebook groups to understand precisely how and why they organized for Duterte. Employing a dualstage thematic analysis on posts and comments by group members between March 28 – May 9, 2016, three key findings emerged. First, motivations for supporting Duterte varied greatly among users and are far more complex than Duterte’s mandate to crack-down on corruption, crime, and drugs. Second, group behavior deviates from top-heavy explanations of online campaign mobilization, as these groups operated autonomously from Duterte’s official campaign. Finally, these groups were not amorphous and had, as the most active members and organizers, certain intermediaries. These grassroots intermediaries sought to amplify support for Duterte by organizing events, using diversionary tactics, and helping to propagate fake news. These findings suggest that while these groups were operating independently, they were not devoid of influence from Duterte’s official social media campaign.