COTS_05_SafetyConcerns

Safety should play a role in the selection of all COTS components in a system.

To ensure proper safety, there are some methods in determining the best recommendations to put forth for COTS selection. Click on each spot to know about them:

 

 

Safety Critical COTS

Most safety standards set requirements to the development process. However, evidence of the development process is often not available to the buyer and user of COTS, as COTS components are usually used as black-box.

Access to the design specifications/code should be granted for safety critical items if at all possible. Communication should be clear and assumptions should be understood completely. The Goal Structuring Notation (GSN) (Wilson, 96) is one example that provides a means for clear communication and understanding.

GSN has been used for writing arguments in safety, dependability, and security within the Nuclear, Defense, Aerospace and Rail industries.

GSN explicitly represents the individual elements of an argument (requirements, claims, evidence and context) and the relationships that exist between these elements (i.e. how individual requirements are supported by specific claims, etc). The principal symbols of the notation are shown below:


Figure 7: The Goal Structuring Notation.