Improved Resource Directory Based on DNS Name Self-Registration for Device Transparent Access in Heterogeneous IoT Networks

With the rapid development of Internet of Things (IoT) technologies in various domains including smart homes, smart cities, smart factories and smart buildings where Internet-connected devices are deployed to provide IoT services based on heterogeneous frameworks and platforms. Many standard protocols, frameworks, libraries and specifications have been proposed for developing IoT applications. Therefore, providing a consistent scheme is important for supporting the interoperability in heterogeneous IoT devices to interact in the same domain and cross-domain. Moreover, supporting the device transparent access for clients to consume IoT service from the different environment that can provide user-friendly service scenarios although the user consumes services in different IoT networks. In this paper, we propose an improved Resource Directory (RD) based on a Domain Name System (DNS) Name Self-Registration (DNSNSR) for the device transparent access in heterogeneous IoT networks. For supporting proposed DNSNSR, an IoT RD is presented based on the Open Connectivity Foundation (OCF) standard specification to provide device registration and discovery service. Through the registration interface, the IoT RD configures the DNS names using Bind 9 to provide the DNS service in an IoT network based on the published device information. Using the discovery interface of RD and name resolution of DNS, the IoT Client gets devices information including (Identifier) ID and Internet Protocol (IP) to access IoT Devices without considering underlying protocols through the interworking proxy of proposed RD in heterogeneous IoT networks. Therefore, the proposed RD based on DNSNSR enables the IoT devices to be discovered by IoT clients in the various environment through the RD and DNS functions. Furthermore, using the OCF-direct and proxy-based access mechanism, the proposed RD based on DNSNSR supports IoT devices to be accessed by clients in various IoT environment.