I decide to use RMI to implement network features. After I finished it, it worked just fine in local mode. But as I deploy class files on the client and the server(different computers) and test it. The server always responds "Connection Refused" to the client. I am sure that I have set the security manager to "java.security.AllPermission" for both client and server. The server also has registerd the service on port 1099. I really don't know why it does not work. Can somebody help me?