(Labelled Transition System Analyser)


LTSA is a verification tool for concurrent systems. It mechanically checks that the specification of a concurrent system satisfies the properties required of its behaviour. In addition, LTSA supports specification animation to facilitate interactive exploration of system behaviour.

A system in LTSA is modelled as a set of interacting finite state machines. The properties required of the system are also modelled as state machines. LTSA performs compositional reachability analysis to exhaustively search for violations of the desired properties. More formally, each component of a specification is described as a Labelled Transition System (LTS), which contains all the states a component may reach and all the transitions it may perform. However, explicit description of an LTS in terms of its states, set of action labels and transition relation is cumbersome for other than small systems. Consequently, LTSA supports a process algebra notation (FSP) for concise description of component behaviour. The tool allows the LTS corresponding to a FSP specification to be viewed graphically.

LTSA has been implemented entirely in Java and may be run either as an applet or a Java application. The button above runs LTSA as an applet. In this mode, LTSA cannot load or save files to local filestore. However, specifications can be pasted into the tool. The examples contained in this document can be run in this way.


User Manual

FSP notation


Copyright 1997 Jeff Magee