Trust Evaluation in Mobile Crowd Sensing Networks Based on Age of Trust (AoT)

Mobile Crowd Sensing (MCS) networks aim to leverage users’ mobile devices to collect environmental or activity information, thereby supporting a wide range of applications. Although large-scale participation of mobile users drives the application and development of MCS networks, it also introduces new security challenges. Due to the diversity and uncertainty of users in MCS networks, trust relationships are difficult to evaluate accurately. This paper introduces the concept of Zero Trust and designs a Zero Trust-based architecture for MCS networks to enhance system security. To address the issue of Zero Trust continuous authentication that consumes network resources and impacts system transmission efficiency, this paper proposes the concept of Age of Trust (AoT), where a higher trust level corresponds to a lower AoT value. The paper tackles the bi-objective optimization problem between the average AoT and throughput on a single link in MCS networks. The results demonstrate that the proposed scheme achieves a reasonable trade-off between security performance and transmission efficiency, showcasing broad application potential in various zero-trust architectures.