Abstract: A method for carrying out the program controlled switching of transmitted data is described. The data are formed into bit groups, and the groups are interleaved within a time division multiplex (t.d.m.) signal frame; the position of the bit group in the frame corresponds to its channel assignment. When bit groups to be switched are received, individually with respect to each line, a request is made to the switching system. Additionally, a feeder channel address is formed from the position of the bit group within the t.d.m. frame, and in at least one coding device assigned to the lines, the feeder line address of the bit group is formed. On the basis of the feeder address (i.e., channel and line address) a feeder cell permanently assigned to each feeder line in a connection store is selected. The bit groups received during the connection establishment stage contain signaling characteristics by means of which the desired trunk address is entered into the feeder cell.