A review on trust management in fog/edge computing: Techniques, trends, and challenges

Cloud computing provides software, infrastructure, and platform as services and reduces the cost of usage for cloud customers. Recently, a system architecture called Fog and Edge Computing (FEC) has been introduced that fills the gap between cloud and things toward the continuum of service and optimizes cloud computing resources by processing time-sensitive data near the data generation source at the network edge. Since the FEC environment includes myriad heterogeneous computing nodes, some of the FEC nodes may be un-trustful or even malicious; therefore, these un-trustworthy nodes could disrupt the normal activity of FEC in data storing and processing. Consequently, FEC trust management is crucial to provide trustworthy data processing and improve user privacy. Despite the critical importance of trust management issues in the FEC, any systematic review in this field has not been performed. This paper presents a systematic review of 74 high-quality articles related to FEC trust management published between 2015 and July 2021. To this end, selected FEC trust management approaches are categorized into three main classes: algorithm, architecture, and model/framework. Additionally, this paper discusses and compares the FEC trust management approaches based on merits and demerits, evaluation techniques, tools and simulation environments, and important trust metrics. Finally, some open issues and future trends for the oncoming studies are highlighted.