yes, it is from a exception, i'm re-using the code on http://www.boost.org/doc/libs/1_40_0/doc/html/boost_asio/example/serialization/client.cpp to implement a co-simulation framework using a famous simulator called network simulator 2, anyway , the runtime error comes when i try to do the connection with the server, the server is open in listening mode but i can not achieved establish the connection.