Flexible Communication Protocol Research Articles

A Flexible Communication Protocol With Guaranteed Determinism for Distributed, Safety-Critical Real-Time Systems

Dependable, safety-critical real-time (SCRT) systems are becoming increasingly important and complex. Examples of such systems are autonomous or self-driving cars which are poised to revolutionise the transport industry. A critical part of these SCRT systems is the network communication protocol that is used by components in an SCRT system to exchange data. Communication protocols for SCRT systems are required to exhibit predictable, worst-case execution times and thus have to be designed in a more static and less flexible way. To ensure this predictability, current state-of-art communication protocols for SCRT systems are based on the Time-Triggered Architecture (TTA), where static and equal-length time-slots are used for all nodes to access the communication channel, irrespective of the size of their transmission payload. This determinism forms the basis of predictable timing, behaviour and fault tolerance. However, this determinism comes at the cost of poor channel and bandwidth utilisation, which hinders the development of SCRT systems. In this paper, we propose a more flexible approach, INCUS+, that allocates the slot length of a node based on its transmission requirements in a Time Division Multiple Access (TDMA) round. We achieve this while retaining the level of dependability required for SCRT systems and ensuring fail-silence. We validate this through formal verification of the timing parameters for the transmission windows of all participating nodes as well as independent bus guardians. Our design exhibits a significant improvement in bandwidth and channel utilisation, as we demonstrate in an autonomous vehicle case study.

Predictive visuo-motor communication through neural oscillations

SummaryThe mechanisms coordinating action and perception over time are poorly understood. The sensory cortex needs to prepare for upcoming changes contingent on action, and this requires temporally precise communication that takes into account the variable delays between sensory and motor processing. Several theorists1,2 have proposed synchronization of the endogenous oscillatory activity observed in most regions of the brain3 as the basis for an efficient and flexible communication protocol between distal brain areas,2,4 a concept known as “communication through coherence.” Synchronization of endogenous oscillations5,6 occurs after a salient sensory stimulus, such as a flash or a sound,7, 8, 9, 10, 11 and after a voluntary action,12, 13, 14, 15, 16, 17, 18 and this directly impacts perception, causing performance to oscillate rhythmically over time. Here we introduce a novel fMRI paradigm to probe the neural sources of oscillations, based on the concept of perturbative signals, which overcomes the low temporal resolution of BOLD signals. The assumption is that a synchronized endogenous rhythm will modulate cortical excitability rhythmically, which should be reflected in the BOLD responses to brief stimuli presented at different phases of the oscillation cycle. We record rhythmic oscillations of V1 BOLD synchronized by a simple voluntary action, in phase with behaviorally measured oscillations in visual sensitivity in the theta range. The functional connectivity between V1 and M1 also oscillates at the same rhythm. By demonstrating oscillatory temporal coupling between primary motor and sensory cortices, our results strongly implicate communication through coherence to achieve precise coordination and to encode sensory-motor timing.

Development of FEB Configuration Test Board for ATLAS NSW Upgrade

The FEB(front end board) configuration test board is developed aiming at meeting the requirement of testing the new generation ASIC(application-specific integrated circuit) chips and its configuration system for ATLAS NSW(New Small Wheel) upgrade, In this paper, some functions are developed in terms of the configurations of the key chips on the FEB, VMM3 and TDS2 using GBT-SCA. Additionally, a flexible communication protocol is designed, verifying the whole data link. It provides technical reference for prototype FEB key chip configuration and data readout, as well as the final system configuration.

A Low Cost Sensor Controller for Health Monitoring

Aging population can benefit from health care systems that allow their health and daily life to be monitored by expert medical staff. Blood pressure, temperature measurements or more advanced tests like Electrocardiograms (ECG) can be ordered through such a healthcare system while urgent situations can be detected and alleviated on time. The results of these tests can be stored with security in a remote cloud or database. Such systems are often used to monitor non-life threatening patient health problems and their advantage in lowering the cost of the healthcare services is obvious. A low cost commercial medical sensor kit has been used in the present work, trying to improve the accuracy and stability of the sensor measurements, the power consumption, etc. This Sensor Controller communicates with a Gateway installed in the patient's residence and a tablet or smart phone used for giving instructions to the patient through a comprehensive user interface. A flexible communication protocol has been defined supporting any short or long term sensor sampling scenario. The experimental results show that it is possible to achieve low power consumption by applying apropriate sleep intervals to the Sensor Controller and by deactivating periodically some of its functionality.

A Component-based Intelligent Seamless Service Migration Mechanism and Flexible Communication Protocol in Pervasive Computing Systems

AbstractIn pervasive computing systems, service selection and fault tolerance are two primary factors, which determines reliability and efficient of service selection system. In this paper, according on ANN-based (Artificial Neural Network) service selection model, we extend the definition and formal description of service, and propose the architecture of service migration system, evaluation method, judgment theorems of triggering and a serviceoriented seamless migration (SOSM) algorithm in pervasive computing systems. We also propose the flexible communication protocol for service seamless migration activity based on mobile agent computing network. We have implemented the SOSM mechanism and flexible communication protocol in an intelligent service selection prototype (ISSPS) system, which provide the pervasive web services for users in pervasive computing environment. The results show that the proposed service migration mechanism is not only reliable but also efficient.

Wireless Technology Applications in Environment and Health: Network Design Challenges

As Wireless applications become more popular in everyday life, the importance of flexible communication protocols rises higher. The limited resources and time-critical nature of wireless sensor networks (WSNs) must be addressed by the network layer, as one of the most mandatory communication components to support routing capabilities in multi-hop mobile sensor nodes' topologies. WSN application particularities are analyzed in order to form the design framework for an adaptive routing algorithm that can address all WSN needs. The routing algorithm can achieve the WSNs objectives with low communication and energy overhead while meeting QoS and congestion requirements. Furthermore, a holistic system-level design approach is followed to integrate network particularities and application requirements and constraints in order to provide a communication-efficient, energy-aware system.

Implementing communication protocols in Java

As the number and variety of Web- and network-based applications continues to increase, so does the need for flexible communication protocols and services to support them. Traditionally, a major impediment to deployment of new protocols and services is the need to upgrade millions of end systems with compatible implementations. At the same time, Java-a language explicitly designed to support development and distribution of new applications via the Web-is emerging as a (potentially) ubiquitous system platform. It is therefore natural to consider whether Java might speed the introduction of protocols to better support new applications. We discuss the suitability of Java as an environment for implementing and deploying communication protocols. Using insights from a Java-based protocol suite and supporting protocol subsystem we have implemented, we describe the benefits of using Java for protocol development and deployment, and how protocol programmers can implement protocols taking advantage of those benefits.

User interface system based on active objects

An active-object user interface system (AOUIS) is a user interface system implemented as an active object system (AOS). An AOS is a transition-based object-oriented system suitable for the design of various concurrent systems. In an AOUIS, user interface objects , which are sometimes called "widgets", are represented as active user interface objects (AUIOs). The behavior of an AUIO is defined by the transition rules, the equational assignment statements, and the event routines provided in its class definition. Furthermore, an AUIO can be constructed from its component AUIOs through structural composition as if it were a hardware object. Thus, AUIOs are better encapsulated and provide more flexible communication protocols than ordinary user interface objects. In addition, declarative descriptions of multiple views can be provided for each AUIO.