Specification Of Communication Protocols Research Articles

A Session Type System for Asynchronous Unreliable Broadcast Communication

Session types are formal specifications of communication protocols, allowing protocol implementations to be verified by typechecking. Up to now, session type disciplines have assumed that the communication medium is reliable, with no loss of messages. However, unreliable broadcast communication is common in a wide class of distributed systems such as ad-hoc and wireless sensor networks. Often such systems have structured communication patterns that should be amenable to analysis by means of session types, but the necessary theory has not previously been developed. We introduce the Unreliable Broadcast Session Calculus, a process calculus with unreliable broadcast communication, and equip it with a session type system that we show is sound. We capture two common operations, broadcast and gather, inhabiting dual session types. Message loss may lead to non-synchronised session endpoints. To further account for unreliability we provide with an autonomous recovery mechanism that does not require acknowledgements from session participants. Our type system ensures soundness, safety, and progress between the synchronised endpoints within a session. We demonstrate the expressiveness of our framework by implementing Paxos, the textbook protocol for reaching consensus in an unreliable, asynchronous network.

Tunable Continuous‐Variable Tripartite Entanglement via Simultaneous and Ordinal Cascaded Nonlinear Processes

AbstractMultipartite quantum entanglement plays a vital role in both fundamental science and quantum applications. The cascaded four‐wave mixing (FWM) process is an effective method to prepare multipartite entanglement, however, the physical nature of entanglement based on different cascading paths, i.e., simultaneous cascaded FWM (SC‐FWM) and ordinal cascaded FWM (OC‐FWM), has not yet been conclusively determined. In this article, tunable continuous‐variable (CV) triple‐mode entanglement is proposed to be generated by using both the SC‐FWM and OC‐FWM schemes. The simulation results reveal that the absorption/dispersion properties of the two nonlinear processes can be efficiently tuned by varying the optical parameters (i.e., the photon detuning and the nonlinear susceptibility), resulting in triple‐mode CV entanglement with tunable properties. Compared with the OC‐FWM scheme, the SC‐FWM scheme has a broader entanglement bandwidth and a higher degree of entanglement, where the tripartite entanglement region is 4.38% larger than that of the OC‐FWM scheme. Furthermore, these results indicate that the SC‐FWM scheme has a more compact and stable mode structure with better entanglement performance. Such tunable optical triple‐mode entanglement may find applications in specific quantum communication protocols and pave the way for implementing and manipulating multichannel quantum networks.

Internet of Things Network Performance: Impact of Message and Client sizes and Reliability Levels

Consistent and timely message transmission is pivotal in the success of Internet of Things (IoT) communications. IoT applications typically involve resourceconstrained devices with limited processing power, memory capacity, and battery life. These characteristics necessitate the use of specialized communication protocols for IoT applications. Message Queue Telemetry Transport (MQTT) is a widely adopted protocol within the IoT ecosystem. Ensuring the appropriate message size and reliability level is crucial for achieving successful MQTT communication. This article empirically assesses MQTT protocol performance across various Quality of Service (QoS) levels while considering different message and client sizes. Initially, we conducted a comparative analysis of message transfer performance between HTTP and MQTT protocols. Subsequently, we delved into the MQTT protocol’s performance across three distinct configurations: one publisher-one subscriber, multiple publishers-one subscriber, and multiple publishersmultiple subscribers. We also examined how message and client sizes impact message transfer latency. When employing a 100-byte payload, we observed that the time delay in a network comprising 150 clients is 60.71% greater than in a network with 50 clients. Similarly, with a message size of 2500 bytes, a network with 50 clients requires 96% less time to deliver than a network with 150 clients.

$ H_\infty $ deployment of nonlinear multi-agent systems with Markov switching topologies over a finite-time interval based on T–S fuzzy PDE control

<abstract><p>The deployment of multi-agent systems (MASs) is widely used in the fields of unmanned agricultural machineries, unmanned aerial vehicles, intelligent transportation, etc. To make up for the defect that the existing PDE-based results are overly idealistic in terms of system models and control strategies, we study the PDE-based deployment of clustered nonlinear first-order and second-order MASs over a finite-time interval (FTI). By designing special communication protocols, the collective dynamics of numerous agents are modeled by simple fist-order and second-order PDEs. Two practical factors, external disturbance and Markov switching topology, are considered in this paper to better match actual situations. Besides, T–S fuzzy technology is used to approximate the unknown nonlinearity of MASs. Then, by using boundary control scheme with collocated measurements, two theorems are obtained to ensure the finite-time $ H_\infty $ deployment of first-order and second-order agents, respectively. Finally, numerical examples are provided to illustrate the effectiveness of the proposed approaches.</p></abstract>

Demonstrating Redundancy Advantages of a Three-Channel Communication Protocol

Multi-Channel communications have the potential to provide advantages in security and redundancy. One widespread example of additional security is the use of 2 Factor Authentication wherein an authorization code is sent via a separate channel. As another example, spread spectrum technology offers resilience against channel interference. However, no currently deployed communication protocols take advantage of the full spectrum of security and performance gains that can be obtained through transmitting data over multiple channels. Taking inspiration from Redundant Array of Inexpensive Disks (RAID) and their use of data striping and mirroring, a secure multi-channel communication protocol was developed that is able to have greater security than an equivalent single channel system while also having greater resiliency against data corruption, therefore requiring fewer, if any, retransmissions than a single channel system when operating in a low availability environment. This approach admittedly comes with significant overhead, both in the use of additional channels and the need for additional processing. Whether the security and availability gains are worth the costs is an open question, with specific answers highly dependent on the particular applications. A specific multi-channel communication protocol, with three independent channels, and incorporating duplication on the bit level, was built and exercised within the OMNeT++ simulation environment in order to examine specific aspects of performance and security of the protocol. This exercise demonstrates that a secure multi-channel protocol operates with less latency than an equivalent single channel system when experiencing less than 50% channel corruption due to adversarial injection, resulting in reduced data loss and need for re-transmissions.

Massive Data Storage Solution for IoT Devices Using Blockchain Technologies.

The Internet of Things (IoT) concept involves connecting devices to the internet and forming a network of objects that can collect information from the environment without human intervention. Although the IoT concept offers some advantages, it also has some issues that are associated with cyber security risks, such as the lack of detection of malicious wireless sensor network (WSN) nodes, lack of fault tolerance, weak authorization, and authentication of nodes, and the insecure management of received data from IoT devices. Considering the cybersecurity issues of IoT devices, there is an urgent need of finding new solutions that can increase the security level of WSNs. One issue that needs attention is the secure management and data storage for IoT devices. Most of the current solutions are based on systems that operate in a centralized manner, ecosystems that are easy to tamper with and provide no records regarding the traceability of the data collected from the sensors. In this paper, we propose an architecture based on blockchain technology for securing and managing data collected from IoT devices. By implementing blockchain technology, we provide a distributed data storage architecture, thus eliminating the need for a centralized network topology using blockchain advantages such as immutability, decentralization, distributivity, enhanced security, transparency, instant traceability, and increased efficiency through automation. From the obtained results, the proposed architecture ensures a high level of performance and can be used as a scalable, massive data storage solution for IoT devices using blockchain technologies. New WSN communication protocols can be easily enrolled in our data storage blockchain architecture without the need for retrofitting, as our system does not depend on any specific communication protocol and can be applied to any IoT application.

Design and implementation of a multi-functional desk lamp with intelligent posture correction based on MCU

With the improvement of people's living standards, more and more people have become accustomed to sitting in front of computers for long periods of time for work or study, which can lead to poor sitting posture habits. This paper aims to design an intelligent desk lamp that combines Bluetooth technology with remote communication technology to improve people's quality of life by correcting sitting posture and providing comfortable lighting experiences. The design uses the STC89C52 as the main control chip, and combines infrared sensing, photoresistor, and Bluetooth HC05 remote communication to detect and control parameters such as human sitting posture and ambient light. Experimental results show that the intelligent desk lamp designed in this paper has excellent lighting effects and can adjust brightness adaptively. In terms of sitting posture correction, the desk lamp can accurately detect human sitting posture and remind users to adjust their posture in a timely manner. In addition, the Bluetooth HC05 remote communication module enables communication with mobile phones and other devices, and facilitates remote control through sending specific AT commands or defining specific communication protocols. The intelligent desk lamp designed in this paper not only improves the comfort and productivity of office environments, but also provides a useful application of smart home technology in daily life. In the future, with the increasing demand for smart home technology, the market prospects of intelligent desk lamps, especially those with remote communication functions, will become even broader.

On Offloading Decision for Mobile Edge Computing Systems Considering Access Reservation Protocol

For several years, mobile edge computing (MEC) has been highlighted as a promising technique to support emerging computation-intensive applications in cellular networks, e.g., 5G and 6G. Most previous studies have mainly focused on jointly optimizing communication (i.e., radio) and computation resources to improve offloading performance without considering specific communication protocols required for operating the MEC systems in practice. In this article, we newly design a contention-based access reservation protocol (ARP) for efficiently supporting simultaneous task offloading requests from a number of edge devices (EDs), and further define necessary signalings required to determine an optimal offloading factor. Thereafter, we formulate an optimization problem to find the optimal offloading factor that minimizes the task-completion latency. Through simulations, we mainly evaluate the task-completion latency performance of the MEC system incorporated with our proposed access reservation protocol under a multiple-input multiple-output (MIMO) environment. Particularly, we thoroughly investigate several practical aspects such as the effect of the number of edge devices attempting to join the task offloading, the number of antennas equipped at the edge device, and the amount of reserved radio resources required for configuring access reservation protocol on the optimal offloading decision. From the results, we verify the validity of our approach, and provide meaningful insights regarding how the network should be configured to fruitfully exploit the offloading with the MEC systems.

Development of a cyber-physical-system perspective based simulation platform for optimizing connected automated vehicles dedicated lanes

Recently, many studies have shown that during the transition period of the coexistence of autonomous vehicles (AVs)/connected automated vehicles (CAVs) and human-driven vehicles (HDVs), a dedicated lane (DL) for AVs/CAVs can improve traffic throughput and lower collision risk, which has become a hot topic in the field of intelligent transportation systems (ITS). This study presents an integrated simulation platform for DL optimization from cyber-physical-system (CPS) perspective. The developed simulation platform can be used to qualitatively and quantitatively evaluate the design parameters, operation modes, contingency plan, etc. of DL in a “What You See Is What You Get (Wysiwyg)” style. First, we introduce the architecture and features of the proposed platform, which comprises of SUMO, OMNeT++, and Unity3D. We implemented all experimental scripts for DL optimization in SUMO, including the configuration of the DLs, car-following models, lane-changing models, vehicle departure models, origin–destination demands, and 2D visualization of traffic flow simulation. We used OMNeT++ for vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication. Unity3D is a 3D visualization platform for simulations synchronized with SUMO. Connected with the driving simulator and paired with a virtual reality (VR) helmet, Unity3D can offer a high-fidelity immersive environment for all types of users. We developed a specific communication protocol to achieve data sharing and synchronization of all components of the proposed simulation platform. Second, this paper depicts the functions of the proposed simulation platform in detail, including the modeling of road networks, vehicles, traffic flow, optimal design, and evaluation indicators of DL. Finally, by using the developed simulation platform, we demonstrated and analyzed three cases: (1) without DL vs with DL, (2) inner lane vs outer lane, and (3) without V2I vs with V2I. The experimental results confirm the feasibility of the developed simulation platform, and yield some interesting findings, such as (1) market penetration rates (MPRs) are an important factor in deciding whether to deploy DLs, (2) the number of lane changes when the vehicle enters/leaves the designated lane is the key criterion for determining the placement of the DLs, and (3) the cooperative vehicle-infrastructure system can offer AVs/CAVs with better over-the-horizon perception capabilities, helping to improve the smoothness of traffic flow in the case of abnormal events. The developed simulation platform is expected to offer a new tool for optimal design and evaluation of DLs for AVs/CAvs.

Comparing Channel Restrictions of Communicating State Machines, High-level Message Sequence Charts, and Multiparty Session Types

Communicating state machines provide a formal foundation for distributed computation. Unfortunately, they are Turing-complete and, thus, challenging to analyse. In this paper, we classify restrictions on channels which have been proposed to work around the undecidability of verification questions. We compare half-duplex communication, existential B-boundedness, and k-synchronisability. These restrictions do not prevent the communication channels from growing arbitrarily large but still restrict the power of the model. Each restriction gives rise to a set of languages so, for every pair of restrictions, we check whether one subsumes the other or if they are incomparable. We investigate their relationship in two different contexts: first, the one of communicating state machines, and, second, the one of communication protocol specifications using high-level message sequence charts. Surprisingly, these two contexts yield different conclusions. In addition, we integrate multiparty session types, another approach to specify communication protocols, into our classification. We show that multiparty session type languages are half-duplex, existentially 1-bounded, and 1-synchronisable. To show this result, we provide the first formal embedding of multiparty session types into high-level message sequence charts.

Wireless communication protocols in smart agriculture: A review on applications, challenges and future trends

IoT based smart agriculture systems are important for efficient usage of lands, water, and energy resources. Wireless communication protocols constitute a critical part of smart agriculture systems because the fields, in general, cover a large area requiring system components to be placed at distant locations. There are various communication protocols with different features that can be utilized in smart agriculture applications. When designing a smart agriculture system, it is required to carefully consider the features of possible protocols to make a suitable and optimal selection. Therefore, this review paper aims to underline the specifications of the wireless communication protocols that are widely used in smart agriculture applications. Furthermore, application-specific requirements, which may be useful during the design stage of the smart agriculture systems, are highlighted. To accomplish these aims, this paper compares the technical properties and investigates the practical applications of five different wireless communication protocols that are commonly used in IoT applications: ZigBee, Wi-Fi, Sigfox, NB-IoT, and LoRaWAN. In particular, the inconsistencies in the technical properties of these protocols reported in different resources have been highlighted and the reason for this situation has been discussed. Considering the features offered by the protocols and the requirements of smart agriculture applications, the appropriateness of a particular protocol to a particular smart agriculture application is examined. In addition, issues about cost, communication quality, and hardware of the five protocols have been mentioned. The trending technologies with high potential for the future applications of smart agriculture have been introduced. In this context, the relation of the technologies like aerial systems, cellular communication, and big data analytics with wireless have been specified. Finally, the leading protocol and the smart agriculture application area have been highlighted through observing the year-based distribution of the recent publications. It has been shown that usage of LoRaWAN protocol has become more widespread in recent years.

P‐100: Driving Technology of Super Large Full In Cell Touch LCD

This paper introduces a self‐contained ultra‐large In Cell Touch driving scheme, which can be applied in 43 inch, 86 inch and larger In Cell Touch products. This driving scheme divides the VCOM electrodes in the liquid crystal cell for traditional LCD into several Sensor blocks, uses display and touch time‐sharing to drive the signal, modulates the signal in Touch stage, and uses special communication protocol to achieve simultaneous touch effect of active pen and finger.

Improved Optimal Path Finding Algorithm of Multistorey Car Park Based on MCP Protocol

To address the urgent issue of car owners wasting a lot of time because they cannot find empty parking spaces in the largely multistorey car park, the paper conceives a solution including algorithm ParkIG. This scheme uses the infrared photoelectric switch to monitor the parking space status. At the same time, we define a special communication protocol named MCP to analyze the parking space data when analyzing the data transmitted by the photoelectric switch. Algorithm ParkIG is used in finding the nearest empty parking space and optimal path planning. Based on the MCP protocol and navigation system, the algorithm ParkIG initially identifies the layer of multistorey where the car is positioned. Our algorithm ParkIG greatly reduces the time and space size of the search domain and update domain when searching for vacant parking spaces in optimal path planning and ends the algorithm running to avoid a lot of computations that are not essential when the algorithm found an optimal path from the entrance to empty of parking space. Simulation experiments show that the performance of our scheme has been significantly improved, such as the time that it takes for the car owner to search for a vacant parking space is decreased by about 25.8% and reduced the space size of search domain and update domain by 70% compared to the algorithm Dijkstra.

How do Hematologists Communicate with Patients Suffering from Chronic Lymphocytic Leukemia?

Chronic Lymphocytic Leukemia (CLL) is a chronic hematologic malignancy with great heterogeneity and unpredictable clinical course. The European Research Initiative on CLL (ERIC), in the context of its CLL Patient Empowerment Program, conducted a study exploring hematologists’ experience of communication. Thirty semi-structured interviews were conducted with hematologists caring for CLL patients in Greece. Inductive thematic qualitative analysis was employed revealing 3 major themes: (i) disclosure of information encompassing ‘negotiating the level of disclosure’, ‘the power of cultural perceptions’, ‘fear of being held culpable’, ‘fear of patients’ and own emotions’; (ii) medical-decision making which described ‘balancing autonomy and beneficence’, ‘considering patients’ preferences’ and ‘adhering to practice guidelines’; (iii) emotional support which included ‘assessment of emotional distress’, ‘identifying and regulating patients’ emotions’ and ‘maintaining a supportive relationship’. In conclusion, physicians are aware of the importance of communication and its potential impact on CLL patients. They use a wide range of communication strategies which serve the diversity of communication goals they must achieve. However, the majority have not received formal education on patient interactions. Present findings highlight the need for specific communication protocols, guidance and training that will empower physicians to overcome challenges, inherent to the nature of CLL.

A Wireless Sensor Network Deployment for Soil Moisture Monitoring in Precision Agriculture.

The use of precision agriculture is becoming more and more necessary to provide food for the world’s growing population, as well as to reduce environmental impact and enhance the usage of limited natural resources. One of the main drawbacks that hinder the use of precision agriculture is the cost of technological immersion in the sector. For farmers, it is necessary to provide low-cost and robust systems as well as reliability. Toward this end, this paper presents a wireless sensor network of low-cost sensor nodes for soil moisture that can help farmers optimize the irrigation processes in precision agriculture. Each wireless node is composed of four soil moisture sensors that are able to measure the moisture at different depths. Each sensor is composed of two coils wound onto a plastic pipe. The sensor operation is based on mutual induction between coils that allow monitoring the percentage of water content in the soil. Several prototypes with different features have been tested. The prototype that has offered better results has a winding ratio of 1:2 with 15 and 30 spires working at 93 kHz. We also have developed a specific communication protocol to improve the performance of the whole system. Finally, the wireless network was tested, in a real, cultivated plot of citrus trees, in terms of coverage and received signal strength indicator (RSSI) to check losses due to vegetation.

The autonomous control of landing on mobile platforms

In this paper, we propose a simulation application that allows an aerial vehicle to land autonomously on a moving platform in the presence of uncertainties and disturbances. We have tested our method with various speeds and positions for the landing platform. In the context of this article, the autonomous control of landing on mobile platforms consists in synchronizing the movement of an aerial vehicle with the movement of the mobile platform. As a first step, the Spacelab INCAS laboratory group has developed an offline simulation application that allows an ABB robot to receive information on the movement of a Stewart-type mobile platform in order to conduct a landing process. The application can initiate a landing process on the mobile platform and guide the vehicle for perfect docking on the platform. Offline simulation allows the study of several scenarios of a robot working cell - the mobile platform before setting up the production cell. The offline application has a distributed client-server structure. The client communicates with the server through specific communication protocols. The client and server can reside on the same computer. The client application is developed in the Matlab environment and has as object the simulation and programming of the PS-6TL-1500 platform; the server one simulates and programs an ABB 7600-500/2.55 robot that moves on the track, in the RAPID language under RobotStudio ABB simulator.

Distributed synchronous diagnosis of discrete event systems modeled as automata

Recently, the decentralized synchronous diagnosis (DESD) method has been proposed for Discrete-Event Systems composed of several modules or subsystems, where the size of the local diagnosers grows linearly with the size of the fault-free behavior models of the system components. Thus, the memory space required to implement the local diagnosers in a computer is reduced in comparison with traditional diagnosis strategies that are based on the composed system model, which may grow exponentially with the number of system modules. The main drawback of the DESD strategy is the possibility of acceptance of an exceeding language as part of the fault-free system behavior by the diagnosis scheme. This exceeding language can be associated with non-detectable faults or an increase in the diagnosis delay bound. In this paper, we propose a distributed synchronous diagnosis (DISD) architecture, where the local diagnosers are implemented considering a specific communication protocol that refines the state estimate of the fault-free behavior of the system modules, leading to a smaller exceeding language accepted as fault-free by the DISD scheme in comparison with the DESD scheme. As in the DESD, in the DISD, the local diagnosers do not grow exponentially with the number of system modules, requiring smaller memory space for implementation than traditional methods. We also define the property of distributed synchronous diagnosability, and propose a verification method.

Packet Analysis: a Model Implementation of a Special Communication Protocol Using Micro Programming

Communication protocols are used in telecommunication systems. These protocols are defined as rules, which enable the entities of communicating systems to transfer information usually as packages. Additionally, each standard communication protocol has uniquely-defined structure and consequently a special pattern of network packets. Here, it is worth mentioning that communication protocols are implemented in different ways, in the system software layer or in hardware layer (silicon chipsets). This paper presents the implementation of a special communication protocol called "Packet Analysis", which is used in the Hardware project "Minimax machine". This implementation is a software that can be written using a special simulator "Minimax simulator", which is the target execution environment. That simulator was successfully developed for micro programming and hardware simulations. In this regard, this study develops an algorithm that represents a step toward simulating communication protocols using micro-programming. The flow chart designed here gives an overview of how the "Packet Analysis" algorithm works (designed protocol), which in turn describes all steps in details. As a result, the entire system of this research paper was implemented and tested with various input values. Additionally, the implemented proposed solution (implemented protocol) was evaluated by two metrics (quantitative measures) using test-benches so that its statistics will be trustworthy for research. Other results of this study showed that there is a lot of scope for optimization in the solution presented in this research paper. This leads in turn to optimize the proposed implementation and to consider implementation alternatives.

Perceptions of the parents of deceased children and of healthcare providers about end-of-life communication and breaking bad news at a tertiary care public hospital in India: A qualitative exploratory study

BackgroundParents of dying children face unique challenge and expect compassionate support from health care providers (HCPs). This study explored the experiences of the parents and HCPs about the end-of-life care and breaking bad news and related positive and negative factors in Indian context.MethodsThis qualitative exploratory study was conducted at paediatrics department of a tertiary care hospital in Delhi. In-depth interviews with the parents (n = 49) and family members (n = 21) of the children died at the hospital and HCPs (6 doctors, 6 nurses and 4 support staffs) were conducted. Also events and communication around death of eight children were observed. Data were inductively analysed using thematic content analysis method to identify emerging themes and codes.ResultsDoctors were the lead communicators. Majority of parents perceived the attitude, communication and language used as by resident doctors as brief, insensitive and sometimes inappropriate or negative. They perceived that the attitude and communication by senior doctor’s as empathetic, positive and complete. Parents recalled the death declaration by resident doctors as non-empathetic, blunt and cold. Most parents received no emotional support from HCPs during and after death of their child. All doctors expressed that death of their patients affected them and their emotions, which they coped through different activities. The overcrowded wards, high workload, infrastructural limitation and no formal communication training added to the emotional stress of the HCPs.ConclusionsMajority of the communication by the HCPs during the hospitalisation and end-of-life period were perceived as suboptimal by the parents. The HCPs were emotionally affected and faced end-of-life communication challenges. The study highlights the communication by HCPs and support for parents during the end-of-life communication and breaking bad news. It suggests adoption of context specific communication protocol and materials and training of HCPs in communication to improve the quality of care.

Deep Learning Anomaly Detection Based on Hierarchical Status-Connection Features in Networked Control Systems

As networked control systems continue to be widely used in large-scale industrial productions, industrial cyber-attacks have become an inevitable problem that can cause serious damage to critical infrastructures. In practice, industrial intrusion detection has been widely acknowledged to detect abnormal communication behaviors. However, unlike traditional IT systems, networked control systems have their own communication characteristics due to specific industrial communication protocols. Thus, simple cyber-attack modeling is inadequate and impractical for high-efficiency intrusion detection because the characteristics of network control systems are less considered. Based on the status information and transmission connection in industrial communication data payloads, which can properly express the characteristics of industrial control logic, this paper associates industrial communication features with transmission connection payload and status payload. Furthermore, transmission connection features include device address, context, time, and packet length, while status features cover measurement, input, distributed state, control state, and more. After designing a convolutional neural network (CNN) and a long short-term memory network (LSTM) to extract status features and transmission connection features from industrial communication data, this paper proposes a hierarchical deep learning anomaly detection approach, which can integrate the advantages of CNN and LSTM to achieve high-efficiency detection. The experimental results clearly show that the proposed approach, having the advantages of strong detection capability and low false alarm rate, is a superior means of anomaly detection when compared to its peers.