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.

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TCP states:

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

this is not big but good one.

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

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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.