Ethernet 10BASE-T1S is an Ethernet variant, mainly intended for automotive applications, that operates at 10 Mbps on a single-pair physical layer. For the half-duplex multidrop topology, the Ethernet 10BASE-T1S standard specifies the Physical Layer Collision Avoidance (PLCA) channel access method, which enables low-latency collision-free cyclic transmissions, but does not implement any mechanism within a node to differentiate between the diverse traffic flows generated. However, in automotive applications Quality of Service (QoS) support is beneficial to meet the requirements of the diverse types of flows. For this reason, this work proposes an application-level traffic shaping mechanism to provide QoS differentiation over Ethernet 10BASE-T1S networks, and discusses the end-to-end delay results obtained via OMNeT++ simulations in a realistic automotive scenario.

Modern automotive systems are evolving towards software-defined vehicles, enabling seamless updates and replacements of software components throughout the vehicle lifecycle. These advancements rely on connected services, making middleware solutions for Service-Oriented Architectures (SoAs) increasingly relevant. Among the various middleware options, MQTT has emerged as a lightweight publish/subscribe protocol. However, MQTT lacks support for prioritizing diverse kinds of communication flows. To address this limitation, a recent work in the literature proposed PrioMQTT, an extended version of MQTT that incorporates message prioritization and adopts the UDP transport protocol to enhance predictability and reduce transmission delays. Despite these enhancements, the centralized broker architecture in MQTT and PrioMQTT can lead to scalability issues under high network loads. This work discusses the challenges and design choices behind a hierarchical version of PrioMQTT, named H-PrioMQTT, that aims to reduce the communication delays in automotive networks handling a large number of flows. Preliminary results obtained through simulations in a realistic in-vehicle scenario show a reduction of the maximum end-to-end delays compared to the plain PrioMQTT.

LoRaWAN supports bi-directional communication, allowing end-devices not only to transmit data to the network server (uplink), but also to receive commands or configuration updates from the network server (downlink). Although most of the research has focused on uplink performance, downlink traffic plays a critical role in enabling control, configuration, and actuation in industrial scenarios. LoRaWAN defines three device classes that offer different Quality of Service (QoS) levels for downlink communication, but they do not specifically address reliability. This work introduces three QoS classes for LoRaWAN downlink that enable configurable trade-offs between reliability and end-device energy consumption. Moreover, this work investigates novel gateway selection strategies that dynamically schedule downlink traffic according to the required QoS levels. Preliminary simulation results show that the proposed strategy significantly improves the packet delivery ratio for downlink transmissions requiring reliability, especially in scenarios with mixed QoS requirements, at the expense of increased energy consumption.

The IEEE 802.3cg-2019 standard defines Ethernet 10BASE-T1S. With a data rate of 10 Mbps in half-duplex mode on a multidrop bus, Ethernet 10BASE-T1S is a suitable candidate for in-vehicle networks with zonal architectures to interconnect multiple sensors with the relevant zonal controller. The standard provides optional Physical Layer Collision Avoidance (PLCA) capabilities that support cyclic transmissions without collisions and provide short transmission delays. However, PLCA lacks explicit priority support, while priority is useful in automotive communications to handle different flows with diverse timing requirements. In this context, this work presents a simulative performance assessment of Ethernet 10BASE-T1S with PLCA enabled in a realistic zonal-based automotive scenario. Moreover, the paper addresses how to leverage the PLCA to offer a better Quality of Service (QoS) to the nodes that generate the most time-critical flows, discussing the delays obtained with different network configurations.

In a LoRaWAN network, a number of end-devices communicate with one or more gateways that forward the messages exchanged between the end-devices and the network server. The LoRaWAN downlink transmissions, i.e., the ones from the network server to the end-devices, have to comply with the strict regional duty cycle constraints that the relevant authorities (e.g., ETSI in Europe) impose on the gateways. However, as the gateways handle the downlink traffic of a large number of end-devices, they reach their duty cycle limits faster than the individual end-devices. This determines a traffic bottleneck, as no downlink transmissions are possible as long as the gateway exceeds the duty cycle limits. Ultimately, this situation can prevent the delivery of important downlinks, e.g., the acknowledgments, in mission-critical applications. This paper explores the rationale behind the introduction of a novel gateway selection strategy, called DL+, that dynamically schedules downlink traffic to enhance the downlink packet delivery ratio. DL+ leverages a weighted decision metrics that takes into account both signal quality parameters, such as RSSI and SNR, and the available duty cycle. Preliminary simulation results are presented that demonstrate the significant improvement of the downlink packet delivery ratio introduced by DL+ compared to existing baseline approaches, especially in dense network scenarios.

Bluetooth Low Energy (BLE) is widely used in several industrial IoT applications to save on costs and power consumption. In this context, to widen the coverage area while meeting the constraints of real-time messages, some applications require multi-hop communications with bounded delays. A few approaches in the literature support real-time traffic on BLE mesh networks, but they use offline configurations, which offer a limited flexibility when new connections are dynamically added based on the application requirements. This paper, instead, proposes a Runtime Connection Admission Control for BLE (RAC-BLE) that allows the BLE devices to accept at runtime new connection requests, provided that the relevant transmissions do not overlap with communications from other BLE devices. This way, RAC-BLE by design provides bounded delays on single-hop transmissions, thus enabling BLE-based real-time mesh networks. The paper provides a detailed description of the RAC-BLE approach, an analytical calculation of the worst case end-to-end delays and experimental performance evaluations. The results show that RAC-BLE significantly reduces the maximum end-to-end delays compared with those obtained by another approach in the literature. For instance, a delay reduction of 70% and 92% is measured in the case of one hop and five hops, respectively.

While the MQTT protocol is widely adopted in IoT applications, its usage for Industrial IoT is prevented by the lack of support for time-critical transmissions. For this reason, recent work has proposed the Prioritized MQTT (PrioMQTT) protocol, i.e., an MQTT extension that introduces message prioritization and schedules messages according to their priority, which reflects their temporal constraints. PrioMQTT succeeds in reducing the latencies of time-critical messages, but it cannot guarantee bounded delays, as the message priorities are not used by the underlying network level. For this reason, this work explores the integration of PrioMQTT with the Time-Sensitive Networking family of standards, in particular with the IEEE 802.1Q-2022, to handle multiple flows with diverse real-time requirements. The work also presents a preliminary experimental assessment on commercial-off-the-shelf devices.

MQTT is an application layer protocol that, thanks to its simplicity and low overhead, is widely used in the Internet of Things (IoT) devices typically found in home automation and consumer applications. The MQTT properties make it an interesting option also for Industrial IoT (IIoT) applications. However, MQTT is not specifically devised for IIoT applications requiring low-latency and the support for time-constrained transmissions. For this reason, this paper proposes an IIoT-enabled version of MQTT called a Prioritized MQTT (PrioMQTT) that is able to provide low latencies to time-critical messages. Unlike the standard MQTT, PrioMQTT adopts the UDP/IP stack, which is more suitable than TCP/IP for low-latency communications. Moreover, PrioMQTT introduces a mechanism to prioritize the time-critical messages over the non-time-critical ones. The combination of the UDP/IP stack and priority support in the PrioMQTT protocol is achieved while maintaining the compliance with the MQTT standard message format. As a result, PrioMQTT can be implemented on commercial-off-the-shelves (COTS) devices without hardware modifications. The paper describes the PrioMQTT protocol and investigates its performance through an assessment in a realistic industrial scenario and in comparison with the standard MQTT protocol.

Bluetooth Low Energy (BLE) is emerging as an appealing solution for several Industrial Internet of Things (IIoT) applications that require low cost and low power consumption. In particular, in this context, some applications need to collect data from sensors distributed over a wide area and require predictable behavior and real-time guarantees for processing such data with bounded delays. For this reason, some works in the literature proposed approaches that enable BLE-based real-time mesh networks. However, these approaches require offline configurations, thus limiting the flexibility and adaptability of the network. This work introduces a solution to build real-time mesh networks by enabling BLE devices to find a suitable configuration at runtime.

Industry 4.0 networks support a broad set of applications and services with diverse requirements on the communication latency and reliability. Thanks to its ability to support long-distance low-power communications with low-cost devices, LoRaWAN represents a very promising solution for Industry 4.0 applications. However, LoRaWAN does not offer different Quality of Service (QoS) classes to meet the diverse requirements of the different flows. This work discusses how to support multiple Medium Access Control (MAC) protocols on a LoRaWAN end-device and introduces flow mapping in LoRaWAN networks, addressing the relevant research challenges and exploring the basic design choices.

The Time-Sensitive Networking (TSN) set of standards allows to support on the same channel the different kinds of traffic flows that are typically found in automotive scenarios. This article proposes the introduction of online Earliest Deadline First-based scheduling in TSN to provide support for event-driven real-time traffic. The proposed approach, called Deadline-TSN, is an online approach, and therefore, unlike other approaches in the literature, it does not require complex offline schedule calculations. Moreover, Deadline-TSN is able to uniformly deal with real-time periodic and event-driven traffic flows. This article presents Deadline-TSN and provides both worst-case response time analysis and simulative assessments in realistic automotive scenarios.

Industrial applications that require low power consumption and wide coverage range may benefit from the adoption of the LoRa communication technology. Unfortunately, the Medium Access Control protocol standardized for LoRa, i.e., LoRaWAN, is not suitable for industrial contexts, as it lacks support for real-time flows. Moreover, to achieve a high number of message transmissions over LoRa while keeping low duty cycle values, a multi-hop communication protocol is required. This work discusses how to combine the support for real-time flows with multi-hop transmissions over LoRa, outlining the basic design choices. A preliminary assessment based on analytical calculations is also provided.

This work explores a network architecture that combines the Software-Defined Networking (SDN) paradigm with a partitioning system for real-time networks based on the Time-Sensitive Networking (TSN) standards. The aim of the addressed architecture is to enforce temporal isolation for the flows already foreseen at the network design time, so that their delays are not affected by the introduction of new flows in the network at run time. The work describes the design of the proposed architecture and presents a preliminary experimental assessment obtained over commercial-off-the-shelf TSN-compliant switches.

The increasing complexity of modern applications calls for more complex embedded computing resources, which integrate several processing units with specialized hardware and virtualization support on a single platform to boost the computation capabilities. These subsystems require a communication system able to support different flows with diverse real-time requirements. In this context, the Time-Sensitive Networking (TSN) family of standards plays an important role. This work proposes the design and the implementation of a framework for enabling TSN communications in heterogeneous platforms with virtualization. Preliminary experimental results are reported, which provide some insights on the limitations and advantages of the proposed framework.

The functionality advancements and novel customer features that are currently found in modern automotive systems require high-bandwidth and low-latency in-vehicle communications, which become even more compelling for autonomous vehicles. In a recent effort to meet these requirements, the IEEE Time-Sensitive Networking (TSN) task group has developed a set of standards that introduce novel features in Switched Ethernet. TSN standards offer, for example, a common notion of time through accurate and reliable clock synchronization, delay bounds for real-time traffic, time-driven transmissions, improved reliability, and much more. In order to fully utilize the potential of these novel protocols in the automotive domain, TSN should be seamlessly integrated into the state-of-the-art and state-of-practice model-based development processes for automotive embedded systems. Some of the core phases in these processes include software architecture modeling, timing predictability verification, simulation, and hardware realization and deployment. Moreover, throughout the development of automotive embedded systems, the safety and security requirements specified on these systems need to be duly taken into account. In this context, this work provides an overview of TSN in automotive applications and discusses the recent technological developments relevant to the adoption of TSN in automotive embedded systems. The work also points at the open challenges and future research directions.

The advent of commercial-off-the-shelf (COTS) heterogeneous multicore platforms is offering many opportunities in the market of embedded computing systems for many application scenarios. The integration of multiple computing elements in a single device entails impressive performance capabilities. At the same time, the increased complexity of emerging systems requires the integration of more subsystems and functionalities, among others the communication subsystem. This work deals with the desirable properties of software transmission mechanisms to enable TSN communications in heterogeneous platforms handled by a hypervisor. Moreover, preliminary simulation results provide some insights on the limits and the advantages of the investigated architectures.

Monitoring of vital parameters plays a key role in better understanding the clinical condition of hospitalized patients. In this perspective, the virtual biosensor for MEDIcal WARNing precursor (MEDIWARN) aims to help the medical team to take a prompt action in response to the evolution of patients' health condition. This paper presents the MEDIWARN network architecture and discusses the design challenges that such a system poses. Simulative assessments provide a preliminary evaluation of the system in realistic scenarios.

Industrial wireless sensor networks (IWSN) are expected to support in the near future a wide range of applications in which mobile nodes, for example, robots or humans, interoperate between them and with machinery. However, the real-time constraints imposed by the industrial processing make mobility support quite challenging. This article proposes an approach based on software-defined networking (SDN), herein named forwarding and time-slotted channel hopping scheduling over SDN (FTS-SDN), that handles transmission scheduling and node mobility in IWSN providing bounded end-to-end delays. The article presents the detailed design of the FTS-SDN and the implementation on commercial-off-the-shelf devices. In addition, the FTS-SDN performance are extensively discussed, providing simulation results and experimental measurements obtained in a real scenario.

One of the main features of future factories envisaged by Industry 4.0 is the integration of humans, machinery and sensors, which will be able to exchange information, trigger actions and collaborate while on the move. The management of Industrial Wireless Sensor Networks (IWSNs) including mobile nodes is a challenging target, as mobility support has a significant impact on the network complexity and management.Recently, Software Defined Networking (SDN) has been proposed as a paradigm for controlling IWSN, with the purpose of providing a smart management of mobile nodes in industrial scenarios. However, resource management, that is, slot and frequency assignment, needs ad hoc clustering strategies to avoid the waste of resources that would impair IWSN scalability. Network scalability is a crucial requisite for the successful development of both IWSN and the Industry 4.0 vision as a whole. For this reason, clustering policies are today a cutting-edge research topic.This paper exploits the SDN approach to manage IWSN and proposes a platform for the evaluation of clustering strategies which can be profitably applied to scalable IWSN that support mobility.

The IEEE 802.15.4 standard contains the specifications of protocols that are suitable for industrial applications. Each of them is tailored for a specific industrial domain. One of these protocols is the Deterministic and Synchronous Multichannel Extension (DSME), which targets general industrial and commercial application domains. The DSME protocol extends the classic IEEE 802.15.4 protocol, overcoming the limitation on the maximum number of Guaranteed Time Slots (GTSs) and providing for channel diversity to increase network robustness. However, the DSME protocol suffers from scalability problems due to the rigid structure of the DSME multi-superframe, which in large networks does not allow to handle GTSs in an efficient way. To overcome this limitation, this work proposes the Shared DSME, an approach to handle the GTSs within the multi-superframe in an efficient way, thus increasing the scalability of the DSME protocol.

Nowadays the role of mobile nodes, either human workers or robots, in industrial production is becoming increasingly important. Consequently, in Industrial Wireless Sensor Networks (IWSN), alongside with reliability and realtime constraints, mobility support is becoming a compelling requirement. However, providing mobility support in IWSN is quite challenging, as the uncertainty and dynamics of industrial environments, combined with the need for supporting real-time constraints of the data and the mobility of the nodes, complicate routing. Software-Defined Networking (SDN) is considered a promising approach for reducing the complexity of network management in many contexts, including industrial automation networks. This paper therefore presents a new SDN approach to handle node mobility and scheduling in IWSN based on the Time Slotted Channel Hopping (TSCH) protocol of the IEEE 802.15.4 standard. The paper describes the proposed approach, that is called the Forwarding and TSCH Scheduling over SDN (FTS-SDN), and provides simulative performance assessments.

Among the Low-Power Wide Area technologies available today, LoRa is one of the most successful, as it enables robust long-distance low-power communications in the unlicensed sub_GHz Industrial, Scientific and Medical band. A number of solution providers and network operators show much interest in this technology for Industry 4.0 applications. In addition, LoRa represent a promising candidate for boosting future Industrial Internet of Things networks and services. However, the current standardized LoRaWAN Medium Access Control (MAC) protocol over LoRa does not fully cope with the requirements of industrial networks, in particular as far as the scheduling of real-time data flow is concerned. To overcome this limitation, this paper proposes Industrial LoRa, a novel medium access strategy for LoRa that enables the implementation of industrial wireless networks for Industrial Internet of Things and Industry 4.0 applications. The paper describes the proposed MAC scheme and the advantages it provides. A simulative assessment shows the performance of the proposed approach in a realistic scenario that is compliant with the requirements of soft real-time applications in Industry 4.0.

Recently, wireless sensor networks (WSNs) are emerging in various application fields thanks to their low cost and ease of deployment. In particular, the rapid increase of critical monitoring applications encourages the study and evaluation of wireless communication protocols that can fulfill the requirements of such applications. Among the WSN standards, the IEEE 802.15.4 is very promising, as it provides critical messages with the support for prioritized channel access through the Priority Channel Access mechanism. The paper assesses the behavior of an IEEE 802.15.4 wireless sensor network implementing the Priority Channel Access mechanism in a realistic monitoring scenario, focusing on the impact on critical message transmissions. The assessments are based on OMNeT++ simulations.

The IEEE Audio Video Bridging (AVB) technology is nowadays under consideration in several automation domains, such as, automotive, avionics, and industrial communications. AVB offers several benefits, such as open specifications, the existence of multiple providers of electronic components, and the real-time support, as AVB provides bounded latency to real-time traffic classes. In addition to the above mentioned properties, in the automotive domain, comparing with the existing in-vehicle networks, AVB offers significant advantages in terms of high bandwidth, significant reduction of cabling costs, thickness and weight, while meeting the challenging EMC/EMI requirements. Recently, an improvement of the AVB protocol, called the AVB ST, was proposed in the literature, which allows for supporting scheduled traffic, i.e., a class of time-sensitive traffic that requires time-driven transmission and low latency. In this paper, we present a schedulability analysis for the real-time traffic crossing through the AVB ST network. In addition, we formally prove that, if the bandwidth in the network is allocated according to the AVB standard, the schedulability test based on response time analysis will fail for most cases even if, in reality, these cases are schedulable. In order to provide guarantees based on analysis test a bandwidth over-reservation is required. In this paper, we propose a solution to obtain a minimized bandwidth over-reservation. To the best of our knowledge, this is the first attempt to formally spot the limitation and to propose a solution for overcoming it. The proposed analysis is applied to both the AVB standard and the AVB ST. The analysis results are compared with the results of several simulative assessments, obtained using OMNeT++, on both automotive and industrial case studies. The comparison between the results of the analysis and the simulation ones shows the effectiveness of the analysis proposed in this work.

Low energy consumption and low cost are some of the primary issues that have to be addressed in Industrial Wireless Sensor Networks (IWSN). Such networks are being increasingly used to acquire sensory data that need to be processed in real-time. The Bluetooth Low Energy (BLE) protocol is an attractive solution for implementing low-cost IWSN with reduced energy consumption and high flexibility. However, the current BLE standard does not provide real-time support for data packets and is limited to a star topology. This paper presents a real-time protocol for industrial wireless mesh networks that is developed on top of the BLE and overcomes these limitations. The paper describes the protocol and provides analysis and experimental results.

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The spread use of IEEE 802.11 networks in industrial automation raised the need to support multiple traffic classes with different requirements. This paper proposes a novel approach, called SchedWiFi, that provides flexible support to the scheduled traffic class, i.e., a high priority traffic class that is transmitted according to a fixed schedule, over IEEE 802.11 ad-hoc industrial networks. SchedWiFi operates on the IEEE 802.11n physical layer, thus providing high datarate, and supports multiple traffic classes with different priorities. SchedWiFi modifies the EDCA mechanism allowing to transmit scheduled traffic without requiring any predefined superframe structure, or timeslots, thus allowing for more flexible schedule of non-ST traffic.

Industrial Wireless Sensor Networks (IWSNs) are found in many application domains that require low latency, robustness, and determinism. The IEEE 802.15.4 standard is not able to cope with the requirements of these applications. For this reason, the IEEE 802.15.4e amendment was introduced, which provides novel MAC-layer profiles that are optimized for a broad range of application domains, including process automation. This paper focuses on two of these profiles, i.e., the Deterministic and Synchronous Multi-channel Extension (DSME) and the Time Slotted Channel Hopping (TSCH). The aim of the paper is twofold. First, assessing their behavior in realistic process automation scenarios. Second, comparing their performance in terms of end-to-end delay, reliability and scalability. The ultimate aim of the work is identifying the limits of those protocols, thus paving the way to further work addressing suitable approaches to tackle them.

Communication networks for cooperative mobile robot applications have to cope with some peculiar requirements that make them quite different from typical MANETs or WSNs. Recent cooperative robot applications envisage the support of low datarate communication technologies, as this choice is beneficial in terms of energy consumption, weight reduction and integration with WSNs. In this context, this paper discusses the design choices behind a novel protocol for cooperating mobile robot applications that operates on low datarate networks and is able to provide bounded latencies, mobility and reliability.

Real-time Ethernet (RTE) technologies are becoming increasingly popular, as they provide high bandwidth and are able to meet the requirements of industrial real-time communications. Among RTE protocols, the EtherCAT standard is suitable for motion control and closed-loop control applications, which require very short cycle times. As EtherCAT was specifically devised for periodic traffic, aperiodic real-time transmissions are far from being efficient, as they entail long cycle times. To overcome this limitation, this paper presents a general framework for priority-driven swapping (PdS)-based scheduling of aperiodic real-time messages over EtherCAT networks, which uniformly covers both dynamic and static priority and allows for very short cycle times. This paper provides a description of the PdS framework, a schedulability analysis for both static priority and dynamic priority scheduling, and simulative assessments obtained through OMNeT++ simulations.

The Low Latency Deterministic Network (LLDN) protocol is defined in the IEEE 802.15.4e, which is an amendment to the IEEE 802.15.4 standard specifically devised to support the requirements of industrial applications. The LLDN provides a TDMA-based medium access mechanism in which the network cycle time grows linearly with the number of nodes. As a result, to offer low cycle times to applications requiring a high number of nodes, the LLDN specifications suggest to create multiple networks operating on different channels by embedding multiple transceivers in the coordinator. However, such an approach entails high costs and increases the design complexity. Moreover, the LLDN protocol foresees a star topology that limits the network area coverage. This paper proposes a novel approach, called a MultiChannel LLDN, based on a hierarchical network structure in which nodes communicate on different channels at the same time. The approach supports a high number of network nodes while maintaining short cycle times without the need for multiple transceivers in the coordinator and also provides backward compatibility with the standard LLDN. The paper presents the MultiChannel LLDN and comparative performance assessments.

The Media Oriented Systems Transport (MOST) network, the current de-facto standard for in-vehicle multimedia and infotainment, does not provide support for the stream priority and serves bandwidth allocation requests based on their arrival order, irrespective of the stream importance. This work proposes a novel bandwidth allocation approach for multimedia streams on MOST150 networks that introduces the stream priority, which is used to reserve bandwidth for each stream according to its importance. The approach also exploits the ability for dynamically changing the bandwidth needs of multimedia streams through variable bitrate compression and is useful in MOST 150 networks supporting, together with multimedia streams, also bandwidth-greedy applications, such as Advanced Driver Assistance Systems.

The IEEE 802.1 Audio/Video Bridging (AVB) protocol successfully supports audio/video streaming over Ethernet networks and is also a promising candidate for industrial automation. However, several industrial automation applications feature requirements that cannot be fulfilled by the current AVB standard. The next generation of IEEE 802.1 standards, which will specifically target the requirements of automotive and industrial control, is under specification within IEEE 802.1 Working Group. Inspired by such an ongoing work, this paper addresses the introduction in IEEE AVB networks of scheduled traffic, i.e., high priority traffic that is transmitted according to a time schedule so as to ensure no interference from other traffic classes. The paper describes the proposed approach, discusses the design choices and presents a performance assessment based on OMNeT++ simulations.

EtherCAT is a real-time Ethernet protocol for factory automation applications that enables periodic data exchange with cycle times of a few microseconds thanks to the capability to process frames “on-the-fly”. EtherCAT does not provide efficient mechanisms for enabling the transmission of asynchronous real-time data from slave nodes. This paper proposes an EDF-based Swapping Approach that allows slaves to send real-time asynchronous traffic over EtherCAT networks in an efficient way, while maintaining the interoperability with standard devices. The paper describes the EDF-based Swapping Approach and presents a comparative performance evaluation with both the EtherCAT standard and an approach in the literature that exploits CAN-Like arbitration.

This paper proposes a three-tiered network architecture to support precision farming applications over large cultivated fields. The hybrid network combines IEEE 802.15.4 Wireless Sensor Networks, operating in a multichannel mode, with Switched Ethernet. The network design has to fulfill several objectives, such as, achieving a tradeoff between energy saving for battery-operated devices and timeliness of precision farming applications over large areas, while providing scalability, robustness and cost efficiency. The work presented in the paper is based on real-world specifications provided by end users, i.e. qualified farmers, during a comprehensive investigation and requirement analysis phase. The paper first discusses the constraints that drive the network design and then presents the three-tiered architecture. Finally, the performance of the network, obtained through OMNeT++ simulations, are discussed.

The PRIME (PoweRline Intelligent Metering Evolution) protocol is a very popular multicarrier narrowband PLC protocol that fits the needs of advanced metering infrastructure applications. This paper proposes a performance assessment of the PRIME MAC layer protocol obtained through OMNeT simulations in different scenarios. The contribution of the paper is twofold. The first contribution is an approach to overcome a well-known problem of discrete-event simulators, i.e., the fact that they do not provide functionalities to emulate the continuous effects of signal propagation. To solve this problem, in this paper the channel is modeled based on measurements, made on real testbeds, so our simulator embeds data taken from experiments performed in a real scenario. The second contribution is the assessment of the impact of the modulation scheme on the performance of the PRIME protocol.

This paper proposes a Lightweight version of the Precision Time Protocol, called L-PTP, for implementation on Powerline communication systems. The aim of this novel protocol is to reduce the number of messages exchanged to achieve synchronization, without penalizing its quality. L-PTP introduces several modifications to the original PTP and can be implemented on COTS devices. The paper focuses on the protocol and on the benefits of its combination with a virtual clock computation performed by a dynamic clock synchronization algorithm.