Finite State Machine of concurrent system

I devise a new algorithm to use flow analysis technique to detect unreachability faults in concurrent systems. I need to find some finite state machine of large concurrent system (probably with hund开发者_StackOverflow中文版reds of states) such as network protocols to do experiments. However, I can't find it on the web. Can anyone give me some clue?

I need state machines that the transitions between them should be synchronized.

Thanks in advance.

TCP states:

http://en.wikipedia.org/wiki/File:Tcp_state_diagram_fixed.svg

this is not big but good one.

Any non-trivial Erlang program. Erlang programs usually consist of hundreds of (potentially concurrent) processes exchanging messages.

I've heard the SIP state machine when used with Reliable Provisional Responses and ICE gets really large. But reconstructing a state diagram from those standards will be time consuming (SIP developers all over the world would be grateful for having such a diagram, if it was correct and complete).

Q.931 (the ISDN UNI protocol) has nice SDL state diagrams. It's only 25 states though.