Second, the basic business editor 1, fixed communication Fixed communication refers to the communication between communication terminal equipment and network equipment mainly through cables or optical cables, so as to realize mutual communication between users. Second, fixed-line domestic long-distance telephone services Fixed-line domestic long-distance telephone services refer to telephone services provided through long-distance telephone networks (including ISDN networks) in different "long-distance number" areas, that is, between different local telephone networks. 3. Fixed-line international long-distance telephone service Fixed-line international long-distance telephone service refers to the international telephone service provided between countries or between countries and regions through international telephone networks (including ISDN networks). Users of domestic telephone network can call users in another country or region by dialing international long-distance prefix and country (region) code. 4.IP telephone service IP telephone service generally refers to the telephone service provided through IP network or through telephone network and IP network. 5. International communication facilities services International communication facilities refer to the ground transmission networks and network elements needed to realize international communication services.