State identification is the well-known problem in the theory of Finite State Machines (FSM) where homing sequences (HS) are used for the identification of a current FSM state, and this fact is widely used in the area of software and hardware testing and verification. For various kinds of FSMs, such as partial, complete, deterministic, non-deterministic, there exist sufficient and necessary conditions for the existence ofpreset and adaptive HS and algorithms for their derivation. Nowadays timed aspects become very important for hardware and software systems and for this reason classical FSMs are extended by clock variables. In this work, we address the problem of checking the existence and derivation of homing sequences for FSMs with timed guards and show that the length estimation for timed homing sequence coincides with that for untimed FSM. The investigation is based on the FSM abstraction of a Timed FSM, i.e. on a classical FSM which describes behavior of corresponding TFSM and inherits some of its properties. When solving state identification problems for timed FSMs, the existing FSM abstraction is properly optimized.
State identification for labeled transition systems with inputs and outputs