Formal method for automated testing data flow aspects of communications protocols, software, and systems specified in Lotos

Formal Method for Automated Transformation of Lotos Specifications to Estelle Specifications

“…The 'Data Oriented'-Restricted Behavior Tree T is a tree that represents both the control flow aspects of the given Lotos specification and the corresponding data flow aspects [8,25]. T is always a finite size tree.…”

“…A normalized specification is a specification in which the Lotos expressions, that are CT Equivalent, have the same syntax. The construction of T is based on the normalized specification obtained from the given specification [8,25]. Given a Lotos specification, the corresponding 'Data Oriented'-Restricted Behavior Tree T is constructed by applying the algorithm given later in this section.…”

“…So, the newly generated node becomes a leaf in T. This facilitates limiting the size of T. If the expressions of two or more of the newly generated nodes are identical or CT Equivalent, we re-label all of them with the same label and extend the tree below only one of them. Then, in a breadth-first manner, we choose the next node for further extension [8,25]. The label of an edge (nl j , nl k ) is the identifier of an event such that el j -event → el k where el j and el k are the expressions represented by the nodes nl j and nl k , respectively.…”