A port setting method of an application system comprises: requesting a naming server for object information corresponding to name information of the other components upon data transmission to the other components; determining whether there exists consistent information based on the object information of the other components received from the naming server; if there exists consistent information, selecting a first and certain protocol, and otherwise, selecting a second protocol; and establishing a connection with the other components by use of the selected protocol. The actual location of the components can be sensed based on Endpoint information of IOR without adding no particular information to the domain profile (xml profile), and a more efficient protocol can be selected depending on the position of each component, thereby enhancing data transmission performance and efficiency in SCA port communications between components.