EN 50128 / 50657
The software safety standard EN 50128 originates from the European Committee for Electrotechnical Standardisation, or CENELEC. Its full title is ‘Railway applications. Communications, signalling and processing systems. Software for railway control and protection systems’. The International published version of the CENELEC EN 50128 standard is IEC 62279. The content of both publications is identical
The standard requires that all systems with safety implications and which contain software should be assigned a Software Integrity Level (SIL), ranging from a value of 0 to 4. The standard then details in a number of ‘normative’ and ‘informative’ ways, the software development activities appropriate to each SIL which should be carried out, and evidence for the completion of which should be generated.
The standard EN 50657:2017 specifies the process and technical requirements for the development of software for programmable electronic systems for use in rolling stock applications. The standard adapts EN 50128:2011 for the application in the Rolling Stock domain, but is shares a lot in common including the definition of the Software Integrity Levels (SIL).
Testing tools for compliance with EN 50128 / 50657 recommendations
QA Systems enables organisations to accelerate EN 50128 / 50657 compliance with automated static analysis and software testing tools:
Tool Certification & Qualification
EN 50128 and 50657 (section 18.104.22.168) states that tools, hardware or software, used for testing shall be shown to be suitable for the purpose. QA Systems’ dynamic testing tool Cantata has been classified and certified by SGS-TÜV GmbH, an independent third party certification body for functional safety, accredited by Deutsche Akkreditierungsstelle GmbH (DAkkS). Cantata has been classified as a class T2 tool, and is usable in development of safety related software according to EN 50128:2011 and 50657:2017 up to Software Safety Integrity Level (SW-SIL) 4.
For our static analysis tool QA-MISRA, our tool Qualification Support Kit (QSK) automatically executes a full tool qualification verification test suite on the installed tool configuration and generates the necessary reports for EN 50128 / 50657 tool qualification.
These tool kits for EN 50128 / 50657 are available to ease our customers’ path to certification. They contain everything needed to prove that Cantata and QA-MISRA provide the required confidence in the use of software tools under EN 50128 / 50657 recommendations as well as comprehensive and detailed guidance on how to use them to comply with the required software verification activities of EN 50128 / 50657.
Please contact us for more information about these certification kits.
Software testing for EN 50128 / 50657 compliance
EN 50128 / 50657 recommends unit and integration testing. Cantata enables developers to verify EN 50128 / 50657 compliant C and C++ code on host native and embedded target platforms.
Cantata helps accelerate compliance with the standard’s software testing requirements by automating:
Start a free trial to evaluate Cantata using your code.
Static Analysis for EN 50128 / 50657 compliance
While Static Analysis is not Mandatory at any EN 50128 / 50657 SIL, it is the only practical way in which a coding standard (which is Mandatory for SIL 3 and 4) can be enforced.
Within the standard, Phase 7.5 (Software Component Implementation and Testing) together with Annex A (Criteria for the Selection of Techniques and Measures) address software development, placing requirements on the initiation of software development; software architectural design and software unit design and implementation. This is the main area where the Static Analysis tools are used; however, some of the information generated from the tools can also be used to assist in later stages, particularly testing.
Please contact us for more information on the static analysis tool QA-MISRA for EN50128 / 50657.
The EN 50128 / 50657 static analysis recommendations by SIL and how these are supported by QA-MISRA and Astrée are summarised in our “QA-MISRA Safety Manual”.
Start a free trial of QA-MISRA to evaluate your code against MISRA, AUTOSAR, CERT C/C++, CWE and other coding standards to ensure automated compliance with ISO EN 50128 / 50657.