Pubblicazioni per 2024

DrATC: Dynamic routing Algorithm based on Trust Characteristics

2024

Cubit Innovation Labs, University of Malaga

Abstract

Authors: Davide Ferraris, Lorenzo Monti

Keywords: Trust, Network, Routing, IoT, Security, Dynamic Routing, BGP, OSPF

In this paper, we propose a dynamic routing algorithm that leverages various trust characteristics to determine the most trusted path in a network. Trust, a multifaceted concept, encompasses attributes such as direct and indirect experiences, transitivity, directionality, context-dependence, and more.

Our approach allows the routing protocol to selectively incorporate these characteristics to enhance the decision-making process. For instance, in scenarios prioritizing direct trust, nodes route packets based solely on direct interactions with their neighbors. In more complex scenarios, both direct and indirect trust are considered, utilizing recommendations from trusted nodes to establish trust with previously un-contacted nodes.

We also explore the use of alternative routes based on specific trust values, ensuring sensitive data is routed through the most trustworthy paths. By integrating these trust metrics, the proposed algorithm dynamically adapts to varying network conditions and requirements, improving the overall reliability and security of the data transmission.

Our experimental results demonstrate the algorithm's effectiveness in selecting trusted paths and highlight the importance of context and adaptability in trust-based routing. This work contributes to the field by providing a flexible and robust framework for incorporating trust into dynamic routing decisions, paving the way for more secure and reliable network communication.

Conference: The 20th International Workshop on Security and Trust Management (STM 2024)

Status: In press

The 20th International Workshop on Security and Trust Management (STM 2024)

Enhancing diffuser performance using transverse grooves to delay flow separation

Alessandro Mariotti, Amedeo Cesare Giovanni Bertini, Gianmarco Lunghi, Giovanni Lombardi, Marco Maganzi, Maurizio Boffadossi, Simone Fenili

2024

Cubit, Ferrari, Politecnico di Milano, Università di Pisa

Abstract

A flow-control method is applied to enhance the efficiency and flow homogeneity of three-dimensional diffusers used in open-jet wind tunnels. Suitably shaped grooves are introduced in the diffuser diverging walls. The grooves promote the relaxation of the non-slip condition along the streamlines bounding the small recirculation regions forming passively inside the grooves. That reduces momentum losses and results in a downstream boundary layer with higher momentum, which is more separation-resistant.

In this study, circular and square-section diffusers with different degrees of flow separation were examined. The grooves significantly enhanced performance in circular diffusers by reducing the extent of separation and promoting an axisymmetric and spatially uniform flow. However, negligible benefits were observed for square-section diffusers. In these cases, since flow separation originates from one of the four inclined edges of the diffuser, placing grooves along the diverging walls does not effectively reduce the separation extent. Nonetheless, the grooves become effective again in diffusers with rectangular cross sections of high aspect ratio.

Conference/Journal: Physics of Fluids 36(10), 105164 (October 2024)

DOI/Source: https://pubs.aip.org/aip/pof/article-abstract/36/10/105164

Keywords: CFD, Computational fluid dynamics, Aerodynamics, Flow control, Boundary layer flow, Turbulent flows

Physics of Fluids