Recently, there has been an increase in studies relating to the Internet of Things (IoT) in various fields, such as smart cities, smart homes, smart factories, and healthcare. In an IoT environment, several entities, including users, devices, and information resources, are interconnected and interworked with services. Therefore, interoperability between different entities is essential to accomplish the goals of IoT systems. Further, security is another important aspect to achieve in an IoT environment to protect information resources and privacy when networking between different entities. Therefore, security and interoperability may be significant barriers in the implementation of IoT in the real world. Several studies have been conducted to investigate methods for accomplishing interoperability and security in IoT, but they address only specific problems. Hence, compatibility and generality must be considered to accomplish the goals of IoT systems. International standards provide general methods by listing protocols, rules, guidelines, and characteristics that are defined and approved by authorized organizations, helping develop and manage systems efficiently by applying these standards; interoperability and security are supported by adopting standards in development and management. Therefore, the adoption of international standards is required to overcome the barriers in IoT. Furthermore, international standard organizations are developing IoT-related standards that may provide a solution to interoperability and security. However, a study focusing on interoperability- and security-related standards has not yet been conducted. Therefore, in this paper, we focus on international standards related to interoperability and security for IoT environments. Moreover, we studied international standard organizations that have been developing standards for IoT. In this study, a systematic literature review is conducted, and international standards are analyzed. In addition, any remaining challenges related to interoperability and security for IoT standards are discussed.

Recently, the integration of state-of-the-art technologies, such as modern sensors, networks, and cloud computing, has revolutionized the conventional healthcare system. However, security concerns have increasingly been emerging due to the integration of technologies. Therefore, the security and privacy issues associated with e-health data must be properly explored. In this paper, to investigate the security and privacy of e-health systems, we identified major components of the modern e-health systems (i.e., e-health data, medical devices, medical networks and edge/fog/cloud). Then, we reviewed recent security and privacy studies that focus on each component of the e-health systems. Based on the review, we obtained research taxonomy, security concerns, requirements, solutions, research trends, and open challenges for the components with strengths and weaknesses of the analyzed studies. In particular, edge and fog computing studies for e-health security and privacy were reviewed since the studies had mostly not been analyzed in other survey papers.

With the continuous improvement of Internet of Things (IoT) technologies, various IoT platforms are under development. However, each IoT platform is developed based on its own device identification system. That is, it is challenging to identify each sensor device between heterogeneous IoT platforms owing to the resource request format (e.g., device identifier) varying between platforms. Moreover, despite the considerable research focusing on resource interoperability between heterogeneous IoT platforms, little attention is given to sensor device identification systems in diverse IoT platforms. In order to overcome this problem, the current work proposes an IoT device name system (DNS) architecture based on the comparative analysis of heterogeneous IoT platforms (i.e., oneM2M, GS1 ‘Oliot’, IBM ‘Watson IoT’, OCF ‘IoTivity’, FIWARE). The proposed IoT DNS analyzes and translates the identification system of the device and resource request format. In this process, resource requests between heterogeneous IoT platforms can be reconfigured appropriately for the resources and services requested by the user, and as a result, users can use heterogeneous IoT services. Furthermore, in order to illustrate the aim of the proposed architecture, the proposed IoT DNS is implemented and tested on a microcomputer. The experimental results show that a oneM2M-based device successfully performs a resource request to a Watson IoT and FIWARE sensor devices.

Due to the rapid development of Internet of Things (IoT), IoT platforms that can provide common functions for things are becoming increasingly important. However, access control frameworks in diverse IoT platforms have been developed for individual security goals, designs, and technologies. In particular, current OAuth-based access control frameworks that are widely used in IoT research have not been providing interoperability among IoT platforms even though sharing resources and services is a critical issue for IoT platforms. Therefore, we analyze the main requirements for an IoT access control framework to properly design our framework and propose an interoperable access control framework based on OAuth 2.0 and Role. Our approach describes a new extended authorization grant flow to issue an Interoperable Access Token (IAT) that has a global access scope across IoT platforms using multiple pairs of clients’ credentials. With the IAT and proposed framework, we can access client-specific domains in heterogeneous IoT platforms, then valuable resources (e.g., data and services) in the domains can be accessed by validating the roles, which will greatly simplify permission management. Furthermore, IAT supports a simple token management (e.g., token issuance, refreshing, and revocation) by managing only one token for diverse IoT platforms. In addition, we implement our interoperable access control framework on Mobius and FIWARE, which are promising open-source IoT platforms, and test an interoperability scenario to demonstrate our approach with the implementation. Furthermore, the proposed framework is compared with other IoT access control approaches based on the selected requirements in this paper.

Internet of Things has become a fundamental paradigm in our everyday lives. However, standards and technologies are often designed without considering interoperability, which is a critical issue for Internet of Things. Internet of Things environment requires interoperability to share resources (e.g. data and services) between heterogeneous Internet of Things domains. The open authorization (OAuth) 2.0 framework that is actively used in Internet of Things (as well as in conventional web environments) also did not focus on interoperability. In other words, the systems that implement the same OAuth 2.0 standard cannot interoperate without additional support. For this reason, we propose an authorization framework as a service. Authorization framework as a service provides an additional authorization layer to support standard authorization capabilities as an interoperable secure wrapper between different domains. Besides, authorization framework as a service supports the four extended authorization grant flow types to issue an interoperable access token, which has a global access scope across multiple heterogeneous domains. With the authorization framework as a service, interoperability can be supported for heterogeneous domains, and token management can also be simple because an interoperable access token can represent several existing access tokens that have local access scopes. Furthermore, this article presents a feasible interoperability scenario, implementation, and security considerations for authorization framework as a service, focusing on Internet of Things platforms.