Thanks a lot for the fast answer.
I have another question about the boost::mutable_buffer since they are used to send and receive payload through the upd socket with the methods send_to and receive_from.
I'd like to know how can I assign the content of a mutable_buffer to a char * ?
I found the method buffer_cast (http://www.boost.org/doc/libs/1_37_0/doc/html/boost_asio/reference/mutable_buffer/buffer_cast.html) but I don't really understand how to use it.