TTE

Fault-tolerant synchronization strategy for Ethernet time
support synchronous time-triggered packet switching

Networks

  • 1553
    1 Mbps serial communication bus to simulate traffic and controller overhead
  • AFDX
    Avionics Full-Duplex Switched Ethernet for use in space and air applications
  • CAN/CAN-FD
    Support automotive and non-automotive applications with flexible gateway
  • FlexRay
    Serial communication link for data communication application
  • Audio-Video Bridging
    Audio and video streams over Ethernet-based networks
  • Time-Sensitive Networking
    Standard technology for deterministic traffic
  • SPI
    Send data between microcontrollers and small peripherals
  • Ethernet-Switched, Gigabit
    Support both local and router designs
  • Token Ring
    Communication protocol used for embedded and SoC architecture
  • Time-Triggered Ethernet
    Fault-tolerant synchronization strategy to synchronize time in Ethernet and support synchronous time-triggered packet switching

Quick Explanation

  • Supports Ethernet MAC layer implementation
  • Supports clock synchronization
  • Supports multicasting
  • Supports traffic shaping

Protocol

  • SAE AS6802

Modal Link

Overview

VisualSim TTEthernet library is completely compliant with TTEthernet specifications. TTEthernet library package includes TTEthernet node, Traffic Generators, TTEthernet Bridge and Statistic generators. In addition to the standard library modules VisualSim also has a pre-configured TTEthernet Configuration tables which includes routing table, Bandwidth allocator, stream table, VLAN table and Traffic generator table. VisualSim TTEthernet library can be used to design a completely new TTEthernet based system or integrate with a system in which multiple different protocols are existing.

Parameters Used

Below is a brief explanation on each TTEthernet library blocks

  • TTE_Node: This block connects TTE_Node to the network. This block manages triple redundancy, multicast, MAC and PHY layers.
  • TTE_Traffic_Gen: This is a traffic generator and it can generate traffic messages with Time-Triggered, Rate Constrained and Best Effort (Normal Ethernet traffic).
  • TTE_Stats: This is a convenient block that displays the latency plot for all streams form all the Nodes, writes the information and warning messages to a file in the model directory, and computes the latency jitters and writes it to a separate file in the Model Directory
  • TTE_Bridge: This block connects to both Nodes and other Bridges. It handles the routing, multicast, compression synchronization and broadcast of clock synchronization messages to all the links.
  • TTE_Setup: One instance of this is required in all TTEthernet models. This processes all the tables in the model.
  • TTE_Config_Table: This is a block that contains the sample of all configuration tables required for TTEthernet

Features

Three message types are provided:

  • Time-Triggered – Messages are sent over the network at predefined times and take precedence over all other message types. The occurrence, temporal delay and precision of time-triggered messages are predefined and guaranteed. The messages have as little delay on the network as possible and their temporal precision is as accurate as necessary. However, “synchronized local clocks are the fundamental prerequisite for time-triggered communication”.
  • Best-effort messages use the remaining bandwidth of the network and have lower priority than the other two types
  • Rate-Constrained – Messages are used for applications with less stringent determinism and real-time requirements. These messages guarantee that bandwidth is predefined for each application and delays and temporal deviations have defined limitsBest-Effort – Messages follow the usual Ethernet policy. There is no guarantee whether and when these messages can be transmitted, what delays occur and if messages arrive at the recipient. .

Time Triggered Ethernet

Time Triggered Ethernet (TTEthernet) was created to provide time triggered communication over Ethernet.

Features:

  • Scalable, open real-time Ethernet platform used for safety-related applications primarily in transportation industries and industrial automation
  • Sets new standards for flexibility, modularity and scalability in Ethernet-based systems
  • Compatible with IEEE 802.3 Ethernet and integrates transparently with Ethernet network components
  • Designed for safe and highly available real-time applications, cyber-physical systems and unified networking
  • Offers deterministic real-time communication and TCP/IP Ethernet traffic in parallel on the same network
  • Simplifies design of fault-tolerant and high availability solutions
  • Innovative technology consolidates experiences and proven mechanisms from aerospace system design, automotive electronics and industrial automation

TTE - Implements Time Triggered Ethernet model