Method for operating a communication network, in particular an Ethernet network, having ring devices (2a-f), which are networked to one another by means of ring lines (4a-e) in a ring topology, wherein the ring devices (2a-f) use a ring redundancy method for transmitting data using a ring redundancy protocol, in which a managing ring device regularly sends test packets via the communication network in both ring directions, said test packets each being received in order by the other ring devices (2b-f) and progressively forwarded from said other ring devices back to the managing ring device so as to detect faults on the communication network, characterized in that a delay in the transmission of a test packet along the ring topology on account of at least one fault packet within the ring topology is prevented by the steps of: a) synchronizing the time of all ring devices (2a-f); b) implementing at least portions of a data traffic scheduling and handling, in particular the complete data traffic scheduling and handling, in accordance with the IEEE 802.1Qbv standard in the applied ring redundancy method by applying at least portions of a time aware shaper method, in particular a complete time aware shaper method, comprising the steps of: b1) sorting all test packets in the individual ring devices (2a-f) into a separate data traffic priority class; b2) allocating an exclusive send queue for the data traffic priority class of the test packets for each ring device (2a-f); b3) defining a protected send time window for the allocated send queue for each ring device (2a-f); and b4) setting up a guard time band at a time immediately before each protected send time window, no data transmission being started within the guard time band, but a data transmission started shortly before the beginning of the guard time band being able to be completed, wherein the transmission of the test packets is scheduled and controlled such that they are each forwarded to the ring devices (2a-f) within the send time window of a ring device (2a-f) at least substantially without a waiting period. a) synchronizing the time of all ring devices (2a-f); b) implementing at least portions of a data traffic scheduling and handling, in particular the complete data traffic scheduling and handling, in accordance with the IEEE 802.1Qbv standard in the applied ring redundancy method by applying at least portions of a time aware shaper method, in particular a complete time aware shaper method, comprising the steps of: b1) sorting all test packets in the individual ring devices (2a-f) into a separate data traffic priority class; b2) allocating an exclusive send queue for the data traffic priority class of the test packets for each ring device (2a-f); b3) defining a protected send time window for the allocated send queue for each ring device (2a-f); and b4) setting up a guard time band at a time immediately before each protected send time window, no data transmission being started within the guard time band, but a data transmission started shortly before the beginning of the guard time band being able to be completed, wherein the transmission of the test packets is scheduled and controlled such that they are each forwarded to the ring devices (2a-f) within the send time window of a ring device (2a-f) at least substantially without a waiting period. b1) sorting all test packets in the individual ring devices (2a-f) into a separate data traffic priority class; b2) allocating an exclusive send queue for the data traffic priority class of the test packets for each ring device (2a-f); b3) defining a protected send time window for the allocated send queue for each ring device (2a-f); and b4) setting up a guard time band at a time immediately before each protected send time window, no data transmission being started within the guard time band, but a data transmission started shortly before the beginning of the guard time band being able to be completed, wherein the transmission of the test packets is scheduled and controlled such that they are each forwarded to the ring devices (2a-f) within the send time window of a ring device (2a-f) at least substantially without a waiting period.