What is the Goal Structuring Notation (GSN)?
The Goal Structuring Notation (GSN) – a graphical argumentation notation – explicitly represents the individual elements of any safety argument (requirements, claims, evidence and context) and (perhaps more significantly) the relationships that exist between these elements (i.e. how individual requirements are supported by specific claims, how claims are supported by evidence and the assumed context that is defined for the argument). The principal symbols of the notation are shown in Figure 1 (with example instances of each concept).