Abstract: In this paper, we describe the design, implementation, and evaluation of a mesh network based messaging application for the One Laptop Per Child XO laptop. We outline the creation of an easy-to-use OLPC Activity that exchanges Ushahidi-style messages with nearby OLPC users through the Internet or a mesh network. Our contributions are to implement an epidemic messaging scheme on mesh networks of OLPC XO laptops, to extend the Ushahidi web application to efficiently exchange messages with nodes in mesh networks, and to allow the Ushahidi server to distribute cures, notifications of message delivery, for each received message. Testing and analysis revealed substantial overhead is introduced by the OLPC's use of Telepathy Salut for activity sharing.

Abstract: When disasters destroy critical communication infrastructure, smartphone-based Delay-Tolerant Networks (DTNs) can provide basic communication for civilians. Although field tests have shown the practicability of such systems, real-world experiments are expensive and hardly repeatable. Simulations are therefore required for the design and extensive evaluation of novel DTN protocols, but meaningful assertions require realistic mobility models for civilians. In this paper, trace files from a large-scale disaster field test are analyzed to identify typical human behavior patterns in a disaster area. Based on this, we derive a novel civilian disaster mobility model that incorporates identified behaviors such as group-based movement and clustering around points-of-interests such as hospitals and shelters. We evaluate the impact of mobility on DTN communication performance by comparing our model with other established mobility models as well as the trace file dataset in a simulative evaluation based on the field test scenario. In general, our mobility model leads to a more realistic assessment of DTN communication performance compared to other mobility models.

Abstract: In the recent months, many measures have been taken by governments to fight the COVID-19 pandemic. Due to the unknown properties of the disease and a lack of experience with handling pandemics, the effectiveness of measures taken was often hard to evaluate the effectiveness of measures, leading to inefficient measures and late execution of efficient measures. Many models have been proposed to evaluate the performance of these measures on the spreading of a pandemic, but these models are commonly vastly simplified and, thus, limited in expressiveness. To extend the expressiveness of the models, we developed a epidemic simulation inside of a flexible and scalable city simulation game to analyse the counter measures to a pandemic in this city and spot common places of infection on a microscopic level. The configurability of our developed epidemic simulation will also be useful for potential future pandemics.