. . "In FIG. 1, numerals 1--1 to 1-M represent broadcast transmission terminals (for example, TV cameras), 4-1 to 4-N represent broadcast reception terminals (for example, TVs), and 20-1 to 20-2 represent ATM switching nodes (or ATM exchanges) connected between the broadcast transmission terminals 1-j (j=1???M where M is a natural number) and the broadcast reception terminal 4-i." . .