A star network (1) having a star coupler (14) and at least a first and second network branch (112, 122), wherein each network branch (112, 122) comprises at least one network node (110, 120) and a bus driver (11, 12) connected between the star coupler (14) and the at least one network node (110, 120). A first bus driver (11) of the first network branch (112) is adapted to detect a symbol pattern comprising at least two predetermined equal control symbols, which are transmitted from the first network node (110) to the second network node (120), wherein a control symbol is part of a control pattern. The control pattern is used to force at least the second network node (120) to switch into a predetermined state. The first bus driver (11) is disabling the first network branch (112) from the star network (1) based on whether the transmitted symbol pattern is detected. By using the protection mechanism a reliable detection of babbling idiots is provided. Moreover, in case of detecting such babbling idiots the remaining network nodes are separated and the network can operate without being influenced by the faulty network node.