Time-Triggered Ethernet Research Articles

Design and Realization of TTE Network based on EDA

The real-time network has always been a hot issue in different kinds of fields. This paper introduced a late-model real-time network, Time-Triggered Ethernet(TTE) with incredible performance of determinacy and reliability. A simulation model of TTE system based on OMNet++ is presented in the paper for validation. Moreover, the paper builds a TTEthernet system based on EDA technology with simplified nodes in which the main synchronization algorithm and some other functions are realized.

Design and simulation of distributed IMA architectures using TTEthernet: a model-driven approach

Integrated modular avionics architectures complemented with time-triggered ethernet (TTEthernet) provides a strong platform to support the design and deployment of distributed avionic software systems. The complexity of the design and continuous integration of such systems can be managed using a model-based methodology. In this paper, we present an extension for the AADL modeling language to support modeling TTEthernet-based distributed systems. This extension consists essentially in a metamodel of the TTEthernet standard and the implementation of its corresponding concrete syntax. Furthermore, we leverage model transformations to enable undertaking the verification of the system models expressed using our AADL extension. In particular, we propose to transform the system model to a model suitable for a simulation using the discrete event system specification formalism. We illustrate the proposed approach using an example of a navigation and guidance system and we use this example to show the verification of the contention-freed property of TTEthernet schedule.

Time-Triggered Ethernet Metamodel: Design and Application

The combination of the SAE Time Triggered Ethernet (TTEthernet) standard with the Integrated Modular Avionics (IMA) architectures supports the design, deployment and integration of mixed-critical avionic applications. In order to cope with the complexity of these tasks, we advocate for a model-driven engineering methodology. The key element of such methodology is the modeling language, which enables producing relevant models of the system. In this paper, we present a metamodel, which captures the main features and concepts defined in the SAE TTEthernet standard. We discuss how a combination of the TTEthernet metamodel with an IMA metamodel can be used to extend the AADL modeling language to model avionic applications deployed a TTEthernet-networked IMA platform. Finally, we present a case study to illustrate our approach.

A Modeling and Verification Approach to the Design of Distributed IMA Architectures Using TTEthernet

Integrated Modular Avionics (IMA) architectures complemented with Time-Triggered Ethernet (TTEthernet) provides a strong platform to support the design and deployment of distributed avionic software systems. The complexity of the design and continuous integration of such systems can be managed using a model-based methodology. In this paper, we build on top of our extension of the AADL modeling language to model TTEthernet-based distributed systems and leverage model transformations to enable undertaking the verification of the system models produced with this methodology. In particular, we propose to transform the system models to a model suitable for a simulation with DEVS. We illustrate the proposed approach using an example of a navigation and guidance system and we use this example to show the verification of the contention-freedom property of TTEthernet schedule.

타임-트리거드 이더넷의 차량네트워크 적용 연구

In this paper, we examine Ethernet based vehicle network which is recently emerging technology. Current MOST for entertainment will be soon replaced with the emerging Ethernet based vehicle network. Although legacy standard Ethernet has several advantages it is not suitable for vehicle backbone network without any modification. As a result, many researches are happening on extending and modification of the Ethernet function for realtime and reliability. Time-triggered Ethernet, one of many trials known as AS6802, is investigated on the architecture and functionalities. We design the traffic model on Time-triggered Ethernet and analyse the latency of the network. We also consider the QoS requirement and environment of operating configuration for vehicle network.

Timing Analysis of TTEthernet Traffic

Over time, more and more systems are becoming mixed-criticality systems. As the complexity and size of these systems grow, computation/communication resources should be more efficient than with traditional systems. Time-triggered (TT) Ethernet is a communication infrastructure that enables the use of a single physical communication infrastructure for distributed mixed-criticality applications while providing timely determinism. TTEthernet distinguishes between two traffic categories: The standard event-triggered (ET) traffic and the TT traffic. The latter, for which higher priority is granted, is subject to strong timing guarantees because of strict-periodicity constraint which fixes start-time cycles of TT messages. In addition, messages in an ET Ethernet traffic, which are of lower priority, have a minimum time interval between their transmission. The focus of this paper is on the timing analysis of a TTEthernet traffic by proposing: (i) A feasibility condition allowing to assess the timing requirements of TT messages. (ii) A schedulability condition allowing to check the schedulability of ET messages by taking into account of TT messages scheduling and idle times.

Enhanced network recovery scheme on real-time switched ethernet for naval combat system

This paper proposes an enhanced network recovery ENR scheme based on switched ethernet to handle network failures in the naval combat system. In this study, network failure recovery is explained through message scheduling on switched ethernet, which is based on previous works on flexible time trigger FTT ethernet. The proposed ENR method expands the previous works by including a revised spanning tree construction scheme and efficient failure detection scheme on real-time switched ethernet for system robustness. To show the advantages of the ENR scheme, the performance of the proposed method is compared with the performance of the existing protocol called time-triggered ethernet TTEthernet. The simulation results show that the proposed ENR scheme outperforms the TTEthernet in terms of the end to end delay and message delivery probability.

Improving Worst-Case Latency Analysis for Rate-Constrained Traffic in the Time-Triggered Ethernet Network

Traditional performance analysis models based on the network calculus approach are not fit for the time-triggered Ethernet (TTEthernet) network due to the porosity characteristic of timed-triggered (TT) traffic in the TT-schedule. This paper introduces the porosity concept into the arrival curve model of TT traffic and gives a general method for the worst-case end-to-end latency analysis of rate-constrained (RC) traffic. Experiments show that our models give tighter latency bounds than results from other already known models and may be used to guide the design of the TT-schedule.

Performance research on time-triggered Ethernet based on network calculus

Abstract In the paper, we research on the performance of time-triggered Ethernet based on network calculus. Three kinds of data with different priority are imported to research on time-triggered Ethernet. Firstly, we adopt network calculus to obtain the theory-bound value of the network performance parameters. Then, we design and implement the time-triggered Ethernet clock synchronization, redundancy fault-tolerant, multi-data communication, service-performance model, node model, and network model successfully in two different topologies. Lastly, we compare the simulation value with the network calculus value and obtain the comparison result. The result shows that the performance parameters of time-triggered Ethernet well meet the theory value, and time-triggered Ethernet specification is feasible.

Dependable and predictable time-triggered Ethernet networks with COTS components

TTEthernet is a cross-industry communication standard that supports the integration of predictable time-triggered communication and event-triggered standard Ethernet traffic. This paper explores the ability of extending the firmware of Commercial-Off-The-Shelf (COTS) routers in order to support TTEthernet. Thereby, we can achieve a significant cost reduction, upgrade existing infrastructures and make field-failure rates of COTS devices available for certification. Based on a generic model of a COTS router, we introduce four methods for extending a COTS router with support for time-triggered and event-triggered message exchanges. The extended COTS router redirects time-triggered messages within pre-planed time intervals, while also processing event-triggered messages when no time-triggered message are scheduled. We achieve temporal predictability and low jitter by minimizing the effect of event-triggered messages onto the timing of time-triggered messages. Furthermore, experimental results from a prototype implementation provide insight into the performance differences between a COTS router and dedicated hardware.

A Clock Synchronization Algorithm for TTEthernet

This paper presents an approach of Time-Triggered Ethernet (TTEthernet, TTE) clock synchronization. Firstly it introduces the roles of each device in clock synchronization algorithm, then analysizes the synchronization steps and their two sub-algorithms:permanencealgorithm andcompressedalgorithm. At last it presents the process of clock correction in different devices.

Real-Time Fault-Tolerant Ethernet Technology - TTEthernet and its Feature

Imported clock synchronization and time-triggered strategy in standard Ethernet, Time-Triggered Ethernet has its unique features. This paper introduces its traffic features, clock synchronization, standard configuration and scheduling strategy. Due to its new features Time-triggered Ethernet will have completely new application areas.

Symmetry Reduction of Time-Triggered Ethernet Protocol

Time-Triggered Ethernet is a relatively new protocol for safety-critical Local Area Network environments, known for its reliability and efficiency in providing seamless fail-safe communication. This paper presents a formal verification of the TTEthernet protocol, based on an interpretation of the TTEthernet specification document, applied to two formal network scenarios that represent a real-time, safety-critical setting. The conceptual model of both scenarios are modeled using the probabilistic timed automata, then, encoded into PRISM code. Also, a set of precise functional requirements is derived from the TTEthernet specification document and expressed using PCTL. Using this approach, the TTEthernet protocol was verified as applied to real-life network environments and one faulty state was identified within one of the settings, thus revealing a possible weak point in TTEthernet protocol.

The case for ethernet in automotive communications

Several factors seem to favor the introduction of Ethernet technology in automotive communications. The spreading of Ethernet as an in-vehicle network for today's cars or for those in the near future is being broadly announced by spokespersons for major carmakers and automotive electronics companies. Even in the scientific community there is a growing interest in the topic, shown by the increasing number of studies on the performance of Ethernet-based technologies such as Switched Ethernet or Time-Triggered Ethernet in automotive embedded systems. This position paper provides an overview on facts and trends towards the introduction of Ethernet in automotive communications and discusses how and to what extent Ethernet technology is likely to step in and provide benefits to the different automotive functional domains. The paper will also discuss which Ethernet technologies would be the possible candidates for the automotive industry.

Time-Triggered Ethernet Using the protocol in vehicle networks

Time-Triggered Ethernet Using the protocol in vehicle networks

The Reference Architecture Template of GENESYS: Cross-Domain Platform Services for Three Levels of Integration

Abstract The reference architecture template of GENESYS provides fundamental architectural services (e. g., communication, configuration, and time services) as the foundation for the implementation and integration of components at chip, device, and system level. The reference architecture template has been designed for multiple application domains, including automotive, avionic, industrial control, and consumer electronic applications. The cross-domain approach results in the ability to exploit the economies of scale, while addressing common challenges of the application domains such as complexity management, robustness and energy efficiency. This paper gives an overview of the reference architecture template and presents instantiations at chip level and system level, namely the Time-Triggered System-on-a-Chip (TTSoC) and Time-Triggered Ethernet (TTE).

Fault and Error Containment of Gateways in Distributed Real-Time Systems

The composition of large embedded computer systems out of heterogenous clusters requires gateways that resolve property mismatches between networks with different communication protocols and diverse computational models. At the same time, fault and error containment mechanisms are needed in order to prevent common mode failures that could be induced by the propagation of faults between clusters. This paper presents gateways to systematically tackle these challenges. The introduced gateways contain structured collections of time-sensitive variables associated with timing information (called a realtime database). The real-time database facilitates fault and error containment by temporally decoupling clusters. For accessing the real-time database from attached networks, we introduce network adaptors that ensure compliance with temporal specifications expressed using state machines with timing constraints. The containment of faults within clusters is of particular importance for mixed-criticality systems and increases the robustness of the overall systems. The proposed solution is experimentally evaluated in an example system with a time-triggered Ethernet network and a Controller Area Network (CAN).

Safety Critical Real-Time Networks Based on Ethernet Technology

As the applications of real-time computing technology are becoming more and more popular in many safety critical domains such as avionics, national defense and transportation systems, field network faces new requirements and challenges because of the coexistence of different kinds of synchronous real-time, asynchronous real-time and non-real-time communication requirements. The realization approach and schedulability analysis of safety critical real-time network are very crucial because of giving a way to solve the problem. Firstly, the shortcomings of the existing COTS network such as Ethernet are described. And then, a high reliable and real time Ethernet communication protocol known as ETTE (event- and time-triggered Ethernet) based on event- and time-triggered approach is presented. The ETTE based real time network is flexible, and the communication time is predictable. At the same time, the network scheduling model is constructed, and the global schedulability analysis is done in this paper. The rationality and feasibility of ETTE protocol is also proven by a concrete example. With ETTE protocol, the diverse requirements of safety critical real time network can be met better. In addition, the ETTE protocol can be widely applied to the field control network of ordinary industry systems.

Safety Critical Real-Time Networks Based on Ethernet Technology

As the applications of real-time computing technology are becoming more and more popular in many safety critical domains such as avionics, national defense and transportation systems, field network faces new requirements and challenges because of the coexistence of different kinds of synchronous real-time, asynchronous real-time and non-real-time communication requirements. The realization approach and schedulability analysis of safety critical real-time network are very crucial because of giving a way to solve the problem. Firstly, the shortcomings of the existing COTS network such as Ethernet are described. And then, a high reliable and real time Ethernet communication protocol known as E&TTE (event- and time-triggered Ethernet) based on event- and time-triggered approach is presented. The E&TTE based real time network is flexible, and the communication time is predictable. At the same time, the network scheduling model is constructed, and the global schedulability analysis is done in this paper. The rationality and feasibility of E&TTE protocol is also proven by a concrete example. With E&TTE protocol, the diverse requirements of safety critical real time network can be met better. In addition, the E&TTE protocol can be widely applied to the field control network of ordinary industry systems.