Thesis for the Degree of Master of Science


Year 2002
Suvi-Maaret Suomalainen

Improving the software processes of safety-related systems

The purpose of this thesis is to create a software process model for a small company delivering safety-related systems. The safety-related systems are delivered to the process and railway industry.

In the literature part, the concepts and the standards of safety-related systems are handled. Conventional software process models are discussed and the eXtreme Programming model is introduced more deeply. Finally, software process improvement and assessment standards; Software Process Improvement and Capability dEtermination and Capability Maturity Model(r) IntegrationSM, are described.

In the beginning of the experimental work, updates have been made to Mipro Oy’‘s quality manual. Based on these updates, the Miso Software Engineering Model has been created. The model is based on the eXtreme Programming model. Some of the practices of eXtreme Programming have been changed, so that the requirements of the standards and for the whole lifecycle of the software have been fulfilled.

The Miso Software Engineering Model is made as user friendly as possible. That is why most of the experimental work has consisted of following Mipro Oy’‘s projects and discussing with Mipro Oy’‘s personnel. The model was partly used in the safety-related system project made for AvestaPolarit.

In the results, an assessment has been made of how well the Miso Software Engineering Model fulfils safety integrity level 3 in the IEC 61508 standard and capability level 2 and 3 in the Software Process Improvement and Capability dEtermination.

Finally, some further research topics have been suggested, which may increase the Miso Software Engineering Model’‘s safety integrity and capability level.

This info last modified 20 Jun 2018 by Jerri Kämpe-Hellenius