Currently the module to server messaging is implemented with kernel sockets. The actual protocol is implemented in the /dax/message.c and /lib/libmsg.c files. I am not sure that I am happy with the low level details at the moment. There are some arbitrary limitations on the size of messages and there is a limit of one server per module too that I may change. To see what is really going on at the moment it would be best to check the latest source code.