IoT Protocols and Cybersecurity Threats

Gordana OSTOJIĆ, Stevan STANKOVSKI

Internet of Things (IoT) represents a heterogeneous network that can integrate different distributed devices. There are several IoT protocols that can be deployed like: MQTT, HTTP, CoAP, BLE and Zigbee. Each protocol has different security measures and vulnerabilities. Analysis shows that there is an increase in cyber attacks on IoT devices in all regions and industry sectors. The increase varies from 6% to 73% from the previous year. This trend is threatening and alarming, indicating the need for deep analysis when deciding what IoT protocol should be used in specific applications. The paper gives a review of IoT protocols analysing security measures and vulnerabilities of mostly used IoT protocols.

Detailed Performance Analysis of Binary Watermarking Algorithm Against Geometric Attacks

Zoran VELIČKOVIĆ, Marko VELIČKOVIĆ, Zoran MILIVOJEVIĆ, Bojan PRLINČEVIĆ

In this paper, the performance of the proposed Binary Watermarking Algorithm against geometric attacks is determined. A QR code encoding important security information was used as a watermark. The performance of the Binary Watermarking Algorithm was determined in the presence of geometric attacks performed by rotating, scaling, and cutting parts of the protected image. The intensity of the attack also varied according to the type of geometrical attack. The proposed Binary Watermarking Algorithm has the possibility of varying the insertion intensity, tests were performed for standard differential threshold values. To present all the obtained results, 3D graphics were created. The obtained results confirm the resistance of the proposed Binary Watermarking Algorithm to certain geometric attacks. Decoding the extracted watermark in the form of a QR code is possible even in case of errors due to the error correction capability of the QR code. The resistance of the Binary Watermarking Algorithm to geometric attacks recommends the use of the proposed algorithm for image protection purposes.

Thermal Anomaly Detection in Unexploded Ordnance Environments

Dejan BLAGOJEVIĆ, Zoran MILIVOJEVIĆ, Milan TANČIĆ, Bojan GLAMOČLIJA, Jelena KRSTIĆ

The main goal of this study is to enhance the method for applying thermal imaging techniques in non-technical terrain reconnaissance where combat operations are conducted and unexploded ordnance (UXO) remnants are present. The study involved conducting thermal image analysis obtained during aerial operations using standard methods within the DJI Thermal Tools environment in combination with elements of two-dimensional Gaussian distribution. This approach was then used to develop decision frameworks for UXO removal. The experiment used a conventional UAV MATRICE 300 RTK DJI rotorcraft equipped with an H20t DJI dual camera and was conducted at the Demining Center of the Republic of Serbia in Grocka.).

ADB Filter for Harmonics Elimination in Frequency-Locked Loops

Zorana MANDIĆ, Nikola KUKRIĆ, Tijana BEGOVIĆ, Marko IKIĆ, Srđan LALE, Slobodan LUBURA

In the context of modern power grids, Frequency-Locked Loops are essential elements for the power converters synchronization. However, the fundamental Frequency-Locked Loop structure shows sensitivity to the presence of DC offset and higher harmonics in the input signal, which can cause oscillations in the estimated grid parameters. This paper presents a new modification of the DC-FLL, resistant to the presence of higher harmonics, by applying an Adaptive Delay Bank filter. This modification has adaptive characteristics thanks to the estimated frequency at the output of the loop, achieving more stable and efficient power converters synchronization with the grid. To evaluate performance, simulations were conducted in the Matlab/Simulink environment.