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In the perspective of the emerging Industrial Internet of things (IIoT), the 6TiSCH working group has been created with the main goal to integrate the capabilities of the IEEE 802.15.4e Time-Slotted Channel Hopping (TSCH) with the IPv6 protocol stack. In order to support time-critical applications in IIoT, reliable real-time communication is a key requirement. Specifically, aperiodic critical traffic, such as emergency alarms, must be reliably delivered to the DODAG root within strict deadline bounds to avoid system failure or safety-critical situations. Currently, there is no mechanism defined in the 6TiSCH architecture for timely and reliably handling of such traffic and its prioritization over the non-critical one. In this paper, we introduce REA-6TiSCH, a reliable emergency-aware communication scheme to support real-time communications of emergency alarms in 6TiSCH networks. In REA-6TiSCH, the aperiodic emergency traffic is opportunistically enabled to hijack transmission cells pre-assigned for the regular periodic traffic in the TSCH schedule. Moreover, we introduce a distributed optimization scheme to improve the probability that an emergency flow is delivered successfully within its deadline bound. To the best of our knowledge, this is the first approach to incorporate emergency alarms in 6TiSCH networks. We evaluate the performance of REA-6TiSCH through extensive simulations and the results show the effectiveness of our proposed method in handling emergency traffic compared to Orchestra scheme. Additionally, we discuss the applicability of REA-6TiSCH and provide guidelines for real implementation in 6TiSCH networks., NIIT

Many emerging Industrial Internet of Things (IIoT) applications involve the use of mobile devices, such as sensors and robots in industrial automation scenarios. Movement of mobile sensor nodes causes intermittent connectivity which in turn deteriorates the network performance in terms of packet loss and delay. The Routing Protocol for Low Power and Lossy Networks (RPL) is introduced as the standard routing protocol for IIoT networks. Although RPL constitutes a reliable and energy-efficient solution for static networks, there is no mechanism defined in the RPL standard of how to support routing in mobile IIoT networks. This paper introduces RMA-RP, a reliable mobility-aware routing protocol to support mobile IIoT networks. RMA-RP utilizes a dynamic motion detection mechanism based on the link quality to cope with topology changes by updating next-hop nodes. Moreover, an adaptive timer is introduced to manage the transmission rate of control messages in order to decrease the network overhead and in turn the energy consumption. We evaluate the performance of RMA-RP through extensive simulations in comparison to existing works and the results demonstrate that RMA-RP has at least 17% higher packet delivery ratio and achieves a reduction of 34% and 51% in terms of delay and network overhead, respectively., Next Generation Industrial IoT (NIIT)

Industrial wireless sensor networks are becoming popular for critical monitoring and control applications in industrial automation systems. For such type of applications, providing reliable real-time performance regarding data delivery is considered as a fundamental challenge. The problem becomes more prominent with mixed-criticality systems, where different data flow with different levels of criticality (importance) coexist and characterized by different requirements regarding delay and reliability. In this paper, we propose a wireless fieldbus protocol to enable real-time communication and service differentiation for cluster-based mixed-criticality networks. A process monitoring scenario of plastic extrusion is used to define the protocol requirements and elaborate the working principle of the proposed work. In our proposed protocol, each data flow is scheduled for channel access based on its criticality level using a distributed prioritized medium access mechanism that ensures a guaranteed channel access for the most critical traffic over other traffic types. The performance of the proposed protocol is analyzed analytically using a discrete-time Markov chain model to evaluate the performance in terms of delay and throughput. Moreover, the extensive simulations are conducted to prove the analytical claims and different performance assessments are provided, which also demonstrate the effectiveness of the proposed approach compared with the related existing work., SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks. This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed. The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wi, SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

This paper proposes a dynamic priority system at medium access control (MAC) layer to schedule time sensitive and critical communications in infrastructure-less wireless networks. Two schemes, priority enabled MAC (PE-MAC) and optimized PE-MAC are proposed to ensure real-time and reliable data delivery in emergency and feedback systems. These schemes use a dynamic priority mechanism to offer improved network reliability and timely communication for critical nodes. Both schemes offer a notable improvement in comparison to the IEEE 802.15.4e low-latency deterministic networks. To ensure more predictable communication reliability, two reliability centric schemes, quality-ensured scheme (QES) and priority integrated QES, are also proposed. These schemes maintain a pre-specified successful packet delivery rate, hence improving the overall network reliability and guaranteed channel access.

This paper proposes a dynamic priority system at medium access control (MAC) layer to schedule time sensitive and critical communications in infrastructure-less wireless networks. Two schemes, priority enabled MAC (PE-MAC) and optimized PE-MAC are proposed to ensure real-time and reliable data delivery in emergency and feedback systems. These schemes use a dynamic priority mechanism to offer improved network reliability and timely communication for critical nodes. Both schemes offer a notable improvement in comparison to the IEEE 802.15.4e low-latency deterministic networks. To ensure more predictable communication reliability, two reliability centric schemes, quality-ensured scheme (QES) and priority integrated QES, are also proposed. These schemes maintain a pre-specified successful packet delivery rate, hence improving the overall network reliability and guaranteed channel access.

The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks. This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed. The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wi, SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

Industrial wireless sensor networks (IWSNs) have the potential to contribute significantly to a variety of wireless sensing endpoints, such as cable replacement, mobility, flexibility and cost reduction. However, the harsh and varied industrial environment entails addressing severe challenges, such as dust, heat, electromagnetic interference (EMI) and radio frequency interference from the other heterogeneous networks. One of the important challenges is the link burstiness in industrial wireless environments, which has not been heavily researched. In this paper, we propose a new timeslot scheduling algorithm to address this problem. The algorithm allows transmissions on the same link to be separated at least by a minimum timeslot distance. Moreover, to provide a synergistic complement to the timeslot scheduling, we also propose a timeslot reuse scheme, which facilitates improved efficiency and reliability in the bandwidth utilization and retransmission and decreases the average delay of the packet arrival. We evaluate the proposed algorithm and scheme by a real implementation, targeting a specific industrial application. The experimental results generally indicate that the proposed media access control (MAC) scheme greatly improves the reliability and decreases the packet arrival delay. Compared with the existing popular methods, the execution of our scheme indicates a minimal link burstiness influence and possesses more efficient bandwidth utilization.

The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks. This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed. The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wi, SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks. This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed. The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wi, SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

The concept of Industrial Internet of Things (IIoT) is the tangible building block for the realisation of the fourth industrial revolution. It should improve productivity, efficiency and reliability of industrial automation systems, leading to revenue growth in industrial scenarios. IIoT needs to encompass various disciplines and technologies to constitute an operable and harmonious system. One essential requirement for a system to exhibit such behaviour is reliable exchange of information. In industrial automation, the information life-cycle starts at the field level, with data collected by sensors, and ends at the enterprise level, where that data is processed into knowledge for business decision making. In IIoT, the process of knowledge discovery is expected to start in the lower layers of the automation hierarchy, and to cover the data exchange between the connected smart objects to perform collaborative tasks. This thesis aims to assist the comprehension of the processes for information exchange in IIoT-enabled industrial automation- in particular, how reliable exchange of information can be performed by communication systems at field level given an underlying wireless sensor technology, and how data analytics can complement the processes of various levels of the automation hierarchy. Furthermore, this work explores how an IIoT monitoring system can be designed and developed. The communication reliability is addressed by proposing a redundancy-based medium access control protocol for mission-critical applications, and analysing its performance regarding real-time and deterministic delivery. The importance of the data and the benefits of data analytics for various levels of the automation hierarchy are examined by suggesting data-driven methods for visualisation, centralised system modelling and distributed data streams modelling. The design and development of an IIoT monitoring system are addressed by proposing a novel three-layer framework that incorporates wi, SMART (Smarta system och tjänster för ett effektivt och innovativt samhälle)

In recent years, many visions for hitherto considered-futuristic computing applications gained momentum. The vision of smart factories is one example for these trends, which all share a common requirement: the prolific dissemination of sensor information. As wireless communication in smart factories needs to cope with harsh environments, the amount of sensor information produced by sources will likely surpass the communication channel's available capacity. This discrepancy calls for efficient communication and filtering protocols, as well as compression mechanisms, as a foundation for dependable applications. We propose such a compression algorithm that is lossless and tailored towards the requirements of the manufacturing industry. Our algorithm employs a two-step stochastic model that uses lossy compression to extract an approximation from the signal and a separate noise model to accommodate the remaining error. Evaluation results validate that our algorithm achieves better compression rates than existing approaches for several types of real world sensor data from the industry., Peer Reviewed

In recent years, many visions for hitherto considered-futuristic computing applications gained momentum. The vision of smart factories is one example for these trends, which all share a common requirement: the prolific dissemination of sensor information. As wireless communication in smart factories needs to cope with harsh environments, the amount of sensor information produced by sources will likely surpass the communication channel's available capacity. This discrepancy calls for efficient communication and filtering protocols, as well as compression mechanisms, as a foundation for dependable applications. We propose such a compression algorithm that is lossless and tailored towards the requirements of the manufacturing industry. Our algorithm employs a two-step stochastic model that uses lossy compression to extract an approximation from the signal and a separate noise model to accommodate the remaining error. Evaluation results validate that our algorithm achieves better compression rates than existing approaches for several types of real world sensor data from the industry., Peer Reviewed, 2017 IEEE 42nd Conference on Local Computer Networks (LCN)

In recent years the advances in wireless sensor networks have grown exponentially and WSNs have been deployed in diverse application areas such as agriculture, disaster management, intelligent transport systems, and industrial automation. In industrial automation, wireless sensor networks have so far mostly been considered within building automation, factory automation, and process automation in order to save cost in cable reduction and maintenance but also improved flexibility [14]. Recently, wireless sensor networks for smart grid applications have been discussed. Several market forecasts have recently predicted exponential growths in the sensor market over the next few years, resulting in a multi-billion dollar market in the near future. For instance, ABI research [18] predicts that in 2015 around 645 million IEEE 802.15.4 chipsets will be shipped and that the worldwide market for automation systems in process industries will grow to roughly $150 billion.

Strict quality of service requirements of industrial applications, challenged by harsh environments and huge interference especially in multi-vendor sites, demand incorporation of cognition in industrial wireless sensor networks (IWSNs). In this paper, a distributed protocol of light complexity for congestion regulation in cognitive IWSNs is proposed to improve the channel utilization while ensuring predetermined performance for specific devices, called primary devices. By sensing the congestion level of a channel with local measurements, a novel congestion control protocol is proposed by which every device decides whether it should continue operating on the channel, or vacate it in case of saturation. Such a protocol dynamically changes the congestion level based on variations of non-stationary wireless environment as well as traffic demands of the devices. The proposed protocol is implemented on STM32W108 chips that offer IEEE 802.15.4 standard communications. Experimental results confirm substantial performance enhancement compared to the original standard, while imposing almost no signaling/computational overhead. In particular, channel utilization is increased by 56% with fairness and delay guarantees. The presented results provide useful insights on low-complexity adaptive congestion control mechanism in IWSNs., QC 20160218

The provision of quality of service for Wireless Sensor Networks is more relevant than ever now where wireless solutions with their flexibility advantages are considered for the extension/substitution of wired networks for a multitude of industrial applications. Scheduling algorithms that give end-to-end guarantees for both reliability and latency exist, but according to recent investigations is the achieved quality of service insufficient for most control applications. Data aggregation is an effective tool to significantly improve on end-to-end contention and energy efficiency compared to single packet transmissions. In practice, though, it is not extensively used for process data processing on the MAC layer. In this paper, we outline the challenges for the use of data aggregation in Industrial Wireless Sensor Networks. We further extend SchedEx, a reliability-aware scheduling algorithm extension, for packet aggregation. Our simulations for scheduling algorithms from the literature show its great potential for industrial applications. Features for the inclusion of data aggregation into industrial standards such as WirelessHART are suggested, and remaining open issues for future work are presented and discussed.

The design of industrial wireless sensor network (IWSN) stacks requires the adoption of real time operation system (RTOS). Challenges exist especially in timing integrity and multi-processor support. As a solution, we propose an RTOS-based architecture for IWSN stacks with multi-processor support. It offers benefits in terms of platform independency, product life cycle, safety and security, system integration complexity, and performance scalability. An implemented WirelessHART stack has proven the feasibility of the proposed architecture in practical product design. And future challenges as well as suggestions to standard improvement are discussed., QC 20131202

With the constant expansion of the industrial monitoring system, there is an urgent requirement to reduce investment and operating costs for the development of industrial communication technology. For industrial real-time monitoring systems, wireless technology can be used in a practical industrial production to take advantages of its flexibility and robustness. As wireless sensor networks have many advantages such as low investment costs, flexible structure and ease of transformation, it has become the focus with regards to industrial areas. THVRG is a routing algorithm that selects the routing path based on two-hop information. Since different information sensed by the sensors may have different requirements in order to reach the sink, a priority-based routing algorithm is required in order to adapt to this kind of situation. This thesis has proposed a priority routing algorithm based on the THVRG (Priority-based THVRG). In addition, a simulation of this algorithm was performed in OPNET. Finally, the report provides an evaluation of the proposed algorithm in industrial wireless sensor networks.

With the constant expansion of the industrial monitoring system, there is an urgent requirement to reduce investment and operating costs for the development of industrial communication technology. For industrial real-time monitoring systems, wireless technology can be used in a practical industrial production to take advantages of its flexibility and robustness. As wireless sensor networks have many advantages such as low investment costs, flexible structure and ease of transformation, it has become the focus with regards to industrial areas. THVRG is a routing algorithm that selects the routing path based on two-hop information. Since different information sensed by the sensors may have different requirements in order to reach the sink, a priority-based routing algorithm is required in order to adapt to this kind of situation. This thesis has proposed a priority routing algorithm based on the THVRG (Priority-based THVRG). In addition, a simulation of this algorithm was performed in OPNET. Finally, the report provides an evaluation of the proposed algorithm in industrial wireless sensor networks.

In any security design, the initial secret distribution for further key management solution is a major step. In industrial wireless sensor networks also, initial bootstrapping of the trust in the system is a major concern. The plant can be assumed to be a closed system, where only authenticated and trusted users are allowed to enter. However, wireless being the broadcast medium, wireless devices need to validate their identity to join the networks. So, there is a need for importing some initial secret key to the devices, so that they can be authenticated during the joining process. The standards for Industrial Wireless Sensor Networks (WirelessHART, ISA100.11a) also have left to the user the initial distribution of the key for joining during device provisioning. In this paper, the current industry practice and the pre-requisite of key distribution in industrial wireless sensor networks is discussed and an outline is presented for future research directions. © 2013 IEEE.

Undergoing developments for the adaptation of Wireless Sensor Networks (WSNs) in automation industry is creating several research questions. The usage of wireless technologies in industrial environments requires real-time reliability and security. Many standards for WSNs and Industrial Wireless Sensor Networks (IWSNs) have been developed. The list includes WirelessHART [4], ISA100.11a [10], Zigbee [16], IEEE 802.15.4, and IEEE 802.15.4a etc.Recently a new network topology “Cell-Based Mesh Networks” [12] has been developed in an effort to make IWSNs feasible for large scale deployments in process automation industries. Cell-Based Mesh Network topology inherits the qualities of star-mesh topology and mesh topology, and also offers many additional features.Reliability of an IWSN significantly depends on the real-time scheduling of the network. During this thesis work a scheduling mechanism has been developed by exploiting the features of a Cell-based Mesh Network. The idea of superframes’ further partitioning into time-cells of 100ms duration is presented, these 100ms time-cells guarantees interlocking data transmission [9] within 100ms. The closed loop control data [9] transmission is guaranteed by assigning dedicated time-slots. The performance evaluation of the presented scheduling mechanism is done by considering two case studies i.e. oil-industry and paper & pulp industry.

Undergoing developments for the adaptation of Wireless Sensor Networks (WSNs) in automation industry is creating several research questions. The usage of wireless technologies in industrial environments requires real-time reliability and security. Many standards for WSNs and Industrial Wireless Sensor Networks (IWSNs) have been developed. The list includes WirelessHART [4], ISA100.11a [10], Zigbee [16], IEEE 802.15.4, and IEEE 802.15.4a etc.Recently a new network topology “Cell-Based Mesh Networks” [12] has been developed in an effort to make IWSNs feasible for large scale deployments in process automation industries. Cell-Based Mesh Network topology inherits the qualities of star-mesh topology and mesh topology, and also offers many additional features.Reliability of an IWSN significantly depends on the real-time scheduling of the network. During this thesis work a scheduling mechanism has been developed by exploiting the features of a Cell-based Mesh Network. The idea of superframes’ further partitioning into time-cells of 100ms duration is presented, these 100ms time-cells guarantees interlocking data transmission [9] within 100ms. The closed loop control data [9] transmission is guaranteed by assigning dedicated time-slots. The performance evaluation of the presented scheduling mechanism is done by considering two case studies i.e. oil-industry and paper & pulp industry.

A growing trend in the automation industry is to use wireless technologies to reduce cable cost, deployment time, unlocking of stranded information in previously deployed devices, and enabling wireless control applications. Despite a huge research effort in the area of wireless sensor networks (WSNs), there are several issues that have not been addressed properly such that WSNs can be adopted properly in the process automation domain. This article presents the major requirements for typical applications in process automation and we also aim to outline the research direction for industrial wireless sensor networks (IWSNs) in industrial automation. The major issues that need to be addressed are safety, security and availability before industrial wireless sensor networks will be adopted in full scale in process automation. © 2011 IEEE., Sponsors: The Institute of Electrical and Electronics Engineers (IEEE); IEEE Industrial Electronics Society (IES); UNINOVA; Universidade Nova de Lisba, Faculdade de Ciencias e Tecnologia; Schneider Electric; O3neida

Wireless sensor networks are becoming more and more popular in a widespread number of applications related to monitoring environments, structures, and machinery. Wired monitoring systems are currently widely adopted in industrial settings due to their reputation and history in performing to established standards. In order to explore the field of low-power wireless industrial sensor network monitoring applications, experimental work has to be done in numerous environments. In this thesis, there is a focus on the design and development of hardware and software for such a purpose. Network coordinator devices capable of Internet connectivity over Ethernet, battery-powered sensor nodes equipped to measure acceleration and temperature, and accelerometer boards were designed and produced for the application. The software on the devices was developed as an adaptation of an open-source operating system, Contiki, and explores Internet version 6 connectivity. The goal of the work on this system is to develop a wireless sensor network platform for future research in the areas of sensor testing and industrial monitoring. Two test networks were created with the aforementioned devices to demonstrate their functionality. One network was formed in a laboratory environment where network performance could be judged and tests could be run efficiently. The network contained nine end-nodes and one gateway, and ran for 49 days with an average packet reception rate of 98.2%. The second network was setup in a compressor room on Queen’s University campus; the topology included four end- ii nodes and one gateway. The network observed continuous data collection for 36 days with an average packet reception rate of 86.6%. The battery replacement cycle for the end-nodes was calculated in-laboratory to be 1.36 years; the platform would be suitable for use in a laboratory setting for future research but more work on the system is necessary to improve performance in an industrial environment. The co, Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2015-10-30 15:58:10.681