Safety Validation

This section applies to ASIL-D or ASIL-B(D) applications. To meet the ASIL-D and ASIL-B(D) safety goals when streaming data with NvSciStream, the application must perform extra validation steps. To ensure the data transmitted between producer and consumer applications are correct, NvSciStream provides a set of *WithCrc APIs to calculate the Cyclic Redundancy Checksum (CRC) values of the important initialization and runtime data and return the CRC values to the applications. In ASIL-D or ASIL-B(D) applications, DriveOS users must use these safe-version APIs for calculating and cross-checking CRC values. The applications are responsible for verifying the CRC values before performing streaming and accessing the buffer data.

In mixed-ASIL configurations where an ASIL-D producer interfaces with lower-ASIL (such as ASIL-B) consumers, consumer-side faults may result in CRC mismatches at the producer end. To maintain Freedom from Interference (FFI), the producer must handle these lower-ASIL CRC failures without degrading ASIL-D use cases. An acceptable mitigation strategy is for the producer to skip validating CRC data from consumers whose ASIL rating is lower than the producer’s ASIL rating.

Use case 3 for the NvSicStream event sample illustrates the validation steps.

• Stream Setup
  • Create Blocks
  • User-defined Endpoint Information
  • Query Connection Index
  • Packet Layout
  • Buffer Objects
  • Synchronization Objects
  • Validation Event
• Streaming
  • Frame Production
  • Frame Consumption
• Stream with Late-Attach/Re-Attach Consumers
• Restrictions for ASIL-D or ASIL-B(D) CRC Validation