Intelligent Requirements Traceability for ISO 26262

Requirements driven development is a foundational component of any safety critical lifecycle, including ISO 26262, the state-of-the-art standard guiding safety in the development of automotive electronic devices. At face value, requirements seem like a very straight forward concept.

1. Project teams write requirements
2. Requirements are implemented into the product
3. The product is tested to ensure the requirements have been met

Challenges

Fortunately, ISO 26262 has provided some guidance in managing requirements, an example being ISO 26262:2018-8 Clause 6. The guidance covers requirement notation, attributes of a safety requirement, and the management of requirements, but even with this information, project teams still face a host of challenges, including:

• Enforcing good requirement structures to make certain they are unambiguous, comprehensible, atomic, feasible, and verifiable
• Configuring workflows that support requirement reviews, approvals, impact analysis, and more
• Capturing and decomposing requirements both within a project and across the supply chain
• Tracing requirements to lifecycle artifacts to prove the requirements are realized and verified (more on this later)

Addressing these challenges is further complicated by the rapid growth in complexity for silicon and systems. Project teams must often manage thousands of requirements and the lifecycle data supporting those requirements. Recognizing this, the ISO 26262 standard went so far as to recommend the use of requirements management tools.

In order to support the management of safety requirements, the use of suitable requirements management tools is recommended.
ISO 26262:2018-8 Clause 6.2

In addition, there are growing software and cybersecurity complexities with the application of standards like ISO 21434 and A-SPICE that must be maintained within requirement and verification cycles. This poses additional challenges when managing processes with full auditable traceability.

The Traceability Challenge

Requirements form the backbone of any safety critical lifecycle, and traceability is a core component. Audits and assessments want to see traceability across multiple areas. This includes not only traceability as requirements are created, reviewed, and approved, but also traceability supporting impact analysis of a requirement change and the ability to perform confirmation measures. When evaluating change impact, this includes viewing what changed, when the requirement changed, who changed the requirement, and finally the rationale behind the change. One of the most challenging aspects of traceability is the management of lifecycle data and linking supporting data to requirements.