ISO 10681-1:2010

Overview

ISO 10681-1:2010, titled Road vehicles - Communication on FlexRay - Part 1: General information and use case definition, is an international standard published by ISO that establishes common requirements for vehicle systems communicating over a FlexRay network. This part of the ISO 10681 series focuses on defining general information, communication scenarios, and use cases relevant to the transport and network layers of FlexRay communication. It supports automotive manufacturers and system developers by providing a standardized framework that drives specific communication capabilities and interface requirements for vehicle communication systems based on FlexRay protocols.

FlexRay communication is key for next-generation automotive electronic systems, providing deterministic, high-speed data transmission important in safety-critical applications such as advanced driver assistance systems (ADAS) and autonomous vehicle functions.

Key Topics

• Communication Layer Scope: ISO 10681-1 addresses the transport and network layers of the OSI model, ensuring interoperability and standardized service across FlexRay vehicle communication links.
• Use Case Definitions: The standard specifies a broad set of communication use cases, enabling the handling of multiple message types, including diagnostics, multimedia, and inter-ECU communication.
• Message Transmission Types:
  • Known data length messages for predictable applications like ECU programming and diagnostics.
  • Unknown but finite message lengths ideal for streamed data applications.
• Reliability Features: Enhanced acknowledgment and retry mechanisms improve data integrity by detecting errors and retransmitting messages from the point of failure.
• Dynamic Frame Handling: Support for variable payload sizes within FlexRay frames optimizes communication efficiency, particularly useful for on-the-fly data routing and streaming.
• Gateway Optimization: Includes mechanisms for routing data between networks with minimal processing, such as on-the-fly routing and direct message forwarding without extensive remapping.
• Parallel ECU Communication: Designed to support simultaneous programming events, enabling flexible bandwidth usage and improved flash programming time.
• Independence from Network Segment Types: The communication layer aims to be agnostic to static or dynamic segment implementation within FlexRay, promoting flexibility in network design.

Applications

• Automotive Electronic Systems: Enables robust and reliable communication for critical vehicle subsystems like powertrain, braking, and safety control units.
• ECU Programming and Diagnostics: Streamlines firmware updates and system health monitoring through defined message protocols and acknowledgment strategies.
• Gateway and Network Integration: Facilitates seamless data exchange between different in-vehicle networks, improving modularity and scalability of vehicle electronics.
• Data Streaming in Vehicles: Supports infotainment and multimedia streaming applications by handling variable data lengths efficiently.
• Advanced Vehicle Architectures: Integral to the implementation of FlexRay-based communication networks in autonomous and semi-autonomous vehicles where timing precision and data integrity are crucial.

Related Standards

• FlexRay Communications System Protocol Specification: Defines the lower-level protocol and data link layer for FlexRay communication.
• ISO/IEC 7498-1 and ISO/IEC 10731: Provide the OSI Basic Reference Model used to structure communication services.
• ISO 10681-2: Specifies communication layer services complementary to Part 1, detailing protocol implementation for FlexRay vehicle networks.
• ISO 14229 Series (Unified Diagnostic Services - UDS): Offers diagnostic services specifications which interface with FlexRay communication layers.
• FlexRay Communications System Electrical Physical Layer Specification: Defines the physical layer requirements for FlexRay networks.

ISO 10681-1:2010 serves as a foundational document for automotive engineers and system integrators designing communication interfaces over FlexRay networks. It ensures that vehicle communication systems meet the necessary reliability, flexibility, and performance standards needed for modern automotive applications and lays the groundwork for subsequent detailed protocol specifications and services.