Airmed: Efficient Self-Healing Network of Low-End Devices

The proliferation of application specific cyber-physical systems coupled with the emergence of a variety of attacks on such systems (malware such as Mirai and Hajime) underlines the need to secure such networks. Most existing security efforts have focused on only detection of the presence of malware. However given the ability of most attacks to spread through the network once they infect a few devices, it is important to contain the spread of a virus and at the same time systematically cleanse the impacted nodes using the communication capabilities of the network. Toward this end, we present Airmed - a method and system to not just detect corruption of the application software on a IoT node, but to self correct itself using its neighbors. Airmed's decentralized mechanisms prevent the spread of self-propagating malware and can also be used as a technique for updating application code on such IoT devices. Among the novelties of Airmed are a novel bloom-filter technique along with hardware support to identify position of the malware program from the benign application code, an adaptive self-check for computational efficiency, and a uniform random-backoff and stream signatures for secure and bandwidth efficient code exchange to correct corrupted devices. We assess the performance of Airmed, using the embedded systems security architecture of TrustLite in the OMNeT++ simulator. The results show that Airmed scales up to thousands of devices, ensures guaranteed update of the entire network, and can recover 95% of the nodes in 10 minutes in both internal and external propagation models. Moreover, we evaluate memory and communication costs and show that Airmed is efficient and incurs very low overhead.Comment: 13 pages, 12 figure

Evaluation of LoRaWAN Wireless Communication Protocol and its applicability in monitoring climate conditions

This work aimed to understand the methodology of implementation of the Internet of Things in Brazil through LoRa technology, which in recent years has shown enormous applicability for remote sensing in several countries around the world. The main characteristics of this type of long distance transmission, such as payload of up to 242 B, transmission rate of 27 kbps, range of up to 30 km, battery life of up to 10 years, node sensitivity of -136 dBm, bandwidth up to 500 kHz and operation in frequency-free spectrum (also known as Industrial Scientific and Medical, or, ISM), are directed to identify that there is an applicability of LoRa in the prevention of natural disasters, urban waste management and productivity in industries or rural areas. Thus, the main focus of this work was to provide a practical contribution to accessible and low cost hardware for the use of LoRa technology in Brazil, prototyping tests of reach, energy efficiency and technical feasibility for the national operation. It was possible to create a reusable programming library (LoBRa) for the hardware used that meets the transmission constraints in accordance with the regulations of the regulatory bodies.Dados abertos - Sucupira - Teses e dissertações (2019