In telecommunication, the term long-haul communications has the following meanings: 1. In public switched networks, pertaining to circuits that span large distances, such as the circuits in inter-LATA, interstate, and international communications. See also Long line (telecommunications) 2. In the military community, communications among users on a national or worldwide basis. Note 2: "Long-haul communications" usually pertains to the U.S. Defense Communications System.