The resource-constrained nature and large-scale adoption of Internet of Things (IoT) have a significant challenge for securing IoT applications. This necessitates a robust and lightweight security architecture and schemes as the existing traditional Internet security architecture and protocols require huge resources and lack of end-to-end security mechanism. In this research, a resource efficient end-to-end security scheme has been proposed by offloading computations and storage of security parameters to fog nodes in the vicinity. In addition, a symmetric-key payload encryption has been used to minimize the overhead of message communication in the resource-contested IoT environment. The analysis shows that the proposed scheme outperforms Transport Layer Security (TLS) in resource usage while it maintains equivalent authenticated end-to-end communication between communicating IoT nodes. The proposed end-to-end security scheme saves more communication bandwidth and incurs less overhead as compared to existing TLS-based security schemes. In particular, the proposed system uses less number of handshakes and achieves a decrease in the number of transmitted messages (approximately 184 bytes as compared to compared TSL message size of 332 bytes) for every handshake. Further, it has been demonstrated through experiments that the proposed security method incurs less overheads as compared to the TLS bandwidth consumption considering a single connection session during message subscription.

IEC 61850 is one of the most prominent communication standards adopted by the smart grid community due to its high scalability, multi-vendor interoperability, and support for several input/output devices. Generic Object-Oriented Substation Events (GOOSE), which is a widely used communication protocol defined in IEC 61850, provides reliable and fast transmission of events for the electrical substation system. This paper investigates the security vulnerabilities of this protocol and analyzes the potential impact on the smart grid by rigorously analyzing the security of the GOOSE protocol using an automated process and identifying vulnerabilities in the context of smart grid communication. The vulnerabilities are tested using a real-time simulation and industry standard hardware-in-the-loop emulation. An in-depth experimental analysis is performed to demonstrate and verify the security weakness of the GOOSE publish-subscribe protocol towards the substation protection within the smart grid setup. It is observed that an adversary who might have familiarity with the substation network architecture can create falsified attack scenarios that can affect the physical operation of the power system. Extensive experiments using the real-time testbed validate the theoretical analysis, and the obtained experimental results prove that the GOOSE-based IEC 61850 compliant substation system is vulnerable to attacks from malicious intruders.

Smart LED streetlight system is one of the enabling technologies for a smart city, giving low-cost, low power outdoor lighting also with benefits for vehicle users as well as pedestrians. Integration of sensors and ZigBee-based wireless sensor modules can furnish an optimal platform for an innovative LED streetlight application. Psychological studies suggest that a different level of color temperature can significantly affect human circadian rhythm. For this reason, correlated color temperature (CCT)-based illumination gives a significant lighting performance both in terms of energy efficiency and in overcoming traffic accidents in low visibility areas. Previous works usually assume only specific platform and did not consider CCT-based illumination toward smart LED streetlight system. In this paper, we consider the importance of CCT-based illumination and propose a novel integration of public weather data awareness, ZigBee-based wireless communication, and dynamic web-based management system for the state-of-art of smart LED streetlight system applicable to smart city. In particular, we design a central web server that can receive weather information and real-time sensor data from each LED streetlights and provides a dynamic and flexible web interface for authorized users. Furthermore, real-time implementation of the proposed system shows perfect transmission-reception parameters, such as throughput and signal strength among the different LED streetlights, which fulfills the wireless communication range and signal quality between each LED streetlights.

Health is a major aspect of life and determines the quality of life. In addition, healthy citizens are more productive and directly influence a country's economy. Thus, for citizens to not get deprived of primary care, it is important to have a proper health monitoring system. For creating such health monitoring system, making use of Internet of Things (IoT) can be the best solution. Fog computing services can be provided to IoT by creating local servers and making use of some computers. Various wireless connectivity solutions being developed have finally given IoT the ability to communicate with each other easily. One such connectivity solution is the Long Range (LoRa) radio which lets IoT communicate over long range with low energy consumption. In this paper, an architecture for smart health monitoring system is proposed and is implemented by creating a basic testbed. The system is an application of IoT deploying LoRa wireless communication under fog computing, benefitting the system with both the qualities of LoRa and fog computing. The test results show that the proposed system can be promising for changing the clinic-centric health system to smart patient-centric health system and for providing seamless health services to all.