The invention relates to a method for monitoring the state of a device within a communication network comprising at least two devices, the network comprising isochronous communication channels transmitting data packets synchronized by a signal emitted by the network emitted in regular time intervals. The method comprises at the level of a first device desiring to be monitored a step of emission by the device being monitored of data packets on a specified isochronous channel in response to the signal emitted regularly by the network. The method also comprises at the level of a second device a step of monitoring the emissions of data packets emitted on the isochronous channel and a step of executing a specified task, consequent upon the absence of data packets on the isochronous channel between at least two emissions of synchronization signals.The invention also relates to a device for the implementation of the method.