started after reaching the search depth. With 100, and a search depth of 100, the maximum number of transitions executed will be 10000. 8.1.9.4 Tree search options Search depth: 100: defines the maximum simulation depth. 8.1.9.5 Power walk options As this algorithm is designed for TTCN test case automatic generation for Autolink, to maximize the SDL symbols coverage, we do not describe its options. 8.1.9.6 Autolink options As Autolink is the tool used for TTCN test case automatic generation, we do not describe its options. 8.1.9.7 Event priorities This is used to change the priority between events during simulation. The default is maximum priority (1) for internal events (inputs and outputs etc.) and channel output (if channel queues are used), and lower priority (2) for input from ENV (input of external signals), timeout events and spontaneous transition (input NONE). The menu command Options1 > Advanced assigns the same priorities to all events, leading to richer behaviors but larger number of global states. Event priorities: 12345 Internal events 10000 Input from ENV 01000 Timeout events 01000 Channel output : 10000 Spontaneous transition : 01000 8.1.9.8 State space generation options Max input port length: 3: maximum number of signals present in each process input queue. Max symbols in transition: 1000: maximum number of symbols in a transition, useful to detect infinite loops within a transition. Scheduling: First: the simulation uses a ready queue to execute first the oldest transition. If changed to all, a more recent transition can be executed first, generally leading to richer behaviors but larger number of global states. Other Simulator Features 277 Transition: SDL: do not use. Max no of instances: 100: do not use (seems equivalent to specifying the maximum number of instances in the process reference in the SDL model). Spont. transition progress: On: means that a spontaneous transition (input none) is considered as progress during nonprogress loop detection. Timer progress: On: means that a timer expir