Fault tolerance for rapidly recovering communication path in a monitoring network of tree topology

Master devices, slave devices, system, and methods thereof in a master-slave tree network are provided. The system comprises a master device and a plurality of slave devices. The method is performed by a first slave device, comprises distributing a first beacon to a second slave device upon determining no beacon being received in a predetermined period; determining a neighboring node from a neighboring node list to establish an alternative connection to the master device, and requesting a new node identifier identifying the first slave device from the master device, thereby completing establishment of the alternative connection.