Modeling the impact of software faults in CCS networks

Software faults appear to be a major source of network outages with the increased deployment of the Common Channel Signaling (CCS) network. Currently, defensive mechanisms against software faults in the implementation of Signalling System Number 7 (SS7) protocol are outside the scope of the SS7 protocol definition. It is demonstrated that the lack of defensive mechanisms to handle certain software faults may lead to networkwide failures. The finite state machine (FSM) representation is used to model the impact of software faults in different critical SS7 protocol functionalities. It is shown that by using the FSM modeling, certain functionalities that could be corrupted in order to test other critical SS7 protocol functions can be identified