Feature interaction detection using backward reasoning with LOTOS

The problem of detecting feature interactions in telephone systems design is addressed. The method proposed involves specification of the features in LOTOS, and uses an analysis technique called backward reasoning. This is is implemented in LOTOS by a combination of backward and forward execution. A tool to help carry out backward execution is presented. A detailed example of the use of the technique is given, involving the three-way-calling and call-waiting features.