The essential component of all the control and sensory systems is a communication layer. The MODBUS protocol used in automation and sensory industry defines a simple format of communication using the master/slave principle, although since it originated in the 1970 it has become obsolete. In this paper, is presented the uBUS protocol as an enhancement of the MODBUS protocol. uBUS protocol proposal brings advanced features for today’s requirements for embedded applications. Enhancements include address extension to 4079 addresses, adding a new communication mode (group broadcast), delegating selected master features to slave, linking with other communication interfaces, and securing communications layer. The main part of this paper deals with the description of design and implementation of the uBUS communication security. An RSA algorithm that uses asymmetric encryption was used to implement communication encryption. This paper presents a way of implementing such encryption and its effectiveness on various types of microcontrollers implementing uBUS slaves. Since the communication protocol security is designed as a separate layer, it is possible to implement different types of encryption.

Serial Communication Protocol With Enhanced Properties–Securing Communication Layer for Smart Sensors Applications

As technology becomes more widely available, millions of users worldwide have installed some form of smart device in their homes or workplaces. These devices are often off-the-shelf commodity systems, such as Google Home or Samsung SmartThings, that are installed by end-users looking to automate a small deployment. In contrast to these “plug-and-play” systems, purpose-built Enterprise Internet-of-Things (E-IoT) systems such as Crestron, Control4, RTI, Savant offer a smart solution for more sophisticated applications (e.g., complete lighting control, A/V management, security). In contrast to commodity systems, E-IoT systems are usually closed source, costly, require certified installers, and are overall more robust for their use cases. Due to this, E-IoT systems are often found in expensive smart homes, government and academic conference rooms, yachts, and smart private offices. However, while there has been plenty of research on the topic of commodity systems, no current study exists that provides a complete picture of E-IoT systems, their components, and relevant threats. As such, lack of knowledge of E-IoT system threats, coupled with the cost of E-IoT systems has led many to assume that E-IoT systems are secure. To address this research gap, raise awareness on E-IoT security, and motivate further research, this work emphasizes E-IoT system components, E-IoT vulnerabilities, solutions, and their security implications. In order to systematically analyze the security of E-IoT systems, we divide E-IoT systems into four layers: E-IoT Devices Layer, Communications Layer, Monitoring and Applications Layer, and Business Layer. We survey attacks and defense mechanisms, considering the E-IoT components at each layer and the associated threats. In addition, we present key observations in state-of-the-art E-IoT security and provide a list of open research problems that need further research. 

/pdf/survey-on-enterprise-internet-of-things-systems-e-iot-a-1urwpha3.pdf

Survey on Enterprise Internet-of-Things systems (E-IoT): A security perspective

As technology becomes more widely available, millions of users worldwide have installed some form of smart device in their homes or workplaces. These devices are often off-the-shelf commodity systems, such as Google Home or Samsung SmartThings, that are installed by end-users looking to automate a small deployment. In contrast to these “plug-and-play” systems, purpose-built Enterprise Internet-of-Things (E-IoT) systems such as Crestron, Control4, RTI, Savant offer a smart solution for more sophisticated applications (e.g., complete lighting control, A/V management, security). In contrast to commodity systems, E-IoT systems are usually closed source, costly, require certified installers, and are overall more robust for their use cases. Due to this, E-IoT systems are often found in expensive smart homes, government and academic conference rooms, yachts, and smart private offices. However, while there has been plenty of research on the topic of commodity systems, no current study exists that provides a complete picture of E-IoT systems, their components, and relevant threats. As such, lack of knowledge of E-IoT system threats, coupled with the cost of E-IoT systems has led many to assume that E-IoT systems are secure. To address this research gap, raise awareness on E-IoT security, and motivate further research, this work emphasizes E-IoT system components, E-IoT vulnerabilities, solutions, and their security implications. In order to systematically analyze the security of E-IoT systems, we divide E-IoT systems into four layers: E-IoT Devices Layer, Communications Layer, Monitoring and Applications Layer, and Business Layer. We survey attacks and defense mechanisms, considering the E-IoT components at each layer and the associated threats. In addition, we present key observations in state-of-the-art E-IoT security and provide a list of open research problems that need further research.

The most common operation of an IoT sensor is that of short activity bursts separated by long time intervals in sleep or listen modes. During the data bursts, sensed information has to be reliably communicated in real time without draining the energy resources of the sensor node. One way to save such resources is to efficiently code the data burst, use single-channel communication, and adopt ultra-low-power communication circuit techniques. Clock-data recovery (CDR) circuits are typically significant consumers of energy on traditional single-channel communication protocols. In this paper, we present a novel single-channel protocol that does not require any CDR circuitry. The protocol is based on the novel concept of a pulsed index where data is encoded to minimize the number of ON bits, move them to the LSB end of the packet, and transmit the ON bit indices in the form of a pulse stream. The pulse count is equal to the index of the ON bit. We call this protocol Pulsed Index Communication (PIC). Beside the elimination of CDR, we show that the implementation of PIC is very area-efficient, low-power and highly tolerant of clocking differences between transmitter and receiver. We present both an FPGA and an ASIC implementation of the protocol and use them to illustrate the performance, reliability and power consumption features of PIC signaling. In particular, we show that for an ASIC implementation on 65nm technology, PIC can reduce area by more than 80% and power by more than 70% in comparison with a CDR-based serial bit transfer protocol.

A pulsed-index technique for single-channel, low-power, dynamic signaling

Industrial control systems (ICS) are being used for surveillance and controlling numerous industrial process plants in national critical infrastructures. Supervisory control and data acquisition (SCADA) system is a core component in ICS systems for continuous monitoring and controlling these process plants. Legacy SCADA systems are working in isolated networks and using proprietary communication protocols which made them less exposed to cyber threats. In recent times, these ICS systems have been connected to Internet and corporate networks for data sharing and remote monitoring. They are also using open protocols and operating systems. This leads to vulnerabilities of the system to cyberattacks. Cybersecurity threats are more prevalent than ever in ICS systems. These attacks may be external or internal. Modbus is a widely deployed communication protocol for SCADA communications. There is no security in design of Modbus protocol, and it is vulnerable to numerous cyberattacks. In this paper, we worked for False Command Injection attack, False Access Injection attack, and replay attacks on Modbus protocol. Initially, a real-time SCADA testbed was set up, and we envisaged the impact of these attacks on Modbus protocol data using the testbed. In this work, we used local area network (LAN) environment only for simulating the attacks. We assumed that the attacks penetrated the LAN network. We proposed and developed (a) a method to detect replay attacks by incorporating time stamp and sequence number in Modbus communications and (b) a frame filtering module which will block unauthorized attacks like False Command Injection and False Access Injection attacks to reach programmable logic controller (PLC). Numbers of attacks were simulated and the performance of the method was measured using attack block rate (ABR). It blocked 97% of malicious Modbus transactions or attacks to reach the PLC. It protects SCADA systems from attackers, which is a core component of industrial control systems. The solution enhanced the security of SCADA systems with Modbus protocol.

/pdf/detection-and-blocking-of-replay-false-command-and-false-1cn587bm3n.pdf

Detection and Blocking of Replay, False Command, and False Access Injection Commands in SCADA Systems with Modbus Protocol

This paper describes the usage of neural networks in microcontrollers for deployment in embedded devices. The issue is focused on the design of a suitable neural network, its optimization and deployment in a 32-bit microcontroller with regards to the limiting factors of the chosen microcontroller. The introductory part of the article is a description of the used technology and hardware on which the solution will be implemented. Accelerometer motion recognition was chosen as a practical application. The proposed solution recognizes 6 basic movements, respectively movement in three axes. Tensorflow and Keras frameworks were used to design and implement a neural network. The created neural network model was after optimization implemented in the firmware of the STM32L4x microcontroller. The proposed solution implements automatic motion detection and its subsequent classification. The proposed principle can be applied to a group of sensors connected to the available interfaces of the microcontroller. Application with an accelerometer can be used to detect specific vibrations, application with MEMS microphones can be used to detect specific sound patterns that indicate a possible fault condition of the monitored device in industry.

Implementation of machine learning algorithm in embedded devices

A considerable funds is spent for the roads maintenance in large areas during the winter. The road maintenance is significantly affected by the temperature change of the road structure. In remote locations may occur a situation, when it is not clear whether the sanding is actually needed because the lack of information on road conditions. In these cases, the actual road conditions are investigated by a personal inspection or by sending out a gritting vehicle. Here, however, is a risk of unnecessary trip the sanding vehicle. This situation is economically and environmentally unfavorable. The proposed system solves the problem of measuring the temperature profile of the road and the utilization of the predictive model to determine the future development trend of temperature. The system was technically designed as a set of sensors to monitor environmental values such as the temperature of the road, ambient temperature, relative air humidity, solar radiation and atmospheric pressure at the measuring point. An important part of the proposal is prediction model which based on the inputs from sensors and historical measurements can, with some probability, predict temperature trends at the measuring point. The proposed system addresses the economic and environmental aspects of winter road maintenance.

Road structural elements temperature trends diagnostics using sensory system of own design

Sensory networks are part of a solution to monitor the required physical variables in the area of interest. Their type, the used communication protocol, plays an important role in the parameter of their complexity. One of the economical solutions is the usage of a 1-wire communication network that requires only 2 physical wires. The individual sensors or the nodes of the communication network are connected in parallel. The goal was to design and implement a universal low-power 1-wire bus module with a fully implemented 1-wire standard. As a platform for the development of such module, STM32-based microcontroller was chosen. The main advantage of this solution is the ability to utilize a sensor from a large variety of available sensors with a standardized communication interface. Our solution of the universal 1-wire module provides a single interface for sensors with different communication interfaces, while it still communicates with the standard 1-wire bus controller.

/pdf/arm-based-universal-1-wire-module-solution-67obsbsxe2.pdf

ARM-Based Universal 1-Wire Module Solution

Measuring systems in industrial environments often require a more types of sensors to refine the quality of environment. Distributed measurement system SenSys is designed to measure 1-wire sensors, but the current offer of sensors despite their undeniable advantages is too narrow. Due to the cost optimization of the necessary cabling of other types of sensors, it is appropriate to use or extend the existing 1-wire network. Extending the measurement system SenSys using solutions based on integrated circuit DS2438 manufactured by Maxim IC retain their benefits of parasitic power connection of sensors in the network with a unique identifier. An example other than measuring temperature is the relative air humidity measurement carried out in office spaces, production or test areas where this is an important parameter. In addition to the hardware extension, it is necessary to include the changes in software for measurement and presentation of the measured data.

http://ieeexplore.ieee.org/iel5/6407297/6415022/06415032.pdf

Gabriel Gaspar

Papers

Serial Communication Protocol With Enhanced Properties–Securing Communication Layer for Smart Sensors Applications

Implementation of machine learning algorithm in embedded devices

Road structural elements temperature trends diagnostics using sensory system of own design

ARM-Based Universal 1-Wire Module Solution

Extension of 1-wire measuring system SenSys