Method for operating an industrial automation system communication network comprising a plurality of communication devices, in which method - at least one control unit (101, 102) controls functions of a plurality of assigned communication devices, and is assigned to at least one partition of the communication network, wherein partitions each comprise specifiable portions of system resources of assigned communication devices for specifiable resource utilization periods, - the communication devices each comprise at least one transceiver, and each transceiver is respectively assigned a plurality of transmit queues, each of which is granted access to the respective transceiver for a definable access time period within a definable repetition cycle, wherein the access time periods and repetition cycles for the transmit queues of the communication devices are controlled by means of a time aware shaper according to IEE 802.1Qbv; wherein, by means of the control unit (101, 102), - the access time periods and repetition cycles for the transmit queues are set in the assigned communication devices by the control unit (101, 102) according to the resource utilization periods for the partitions, - the partitions are classified according to the access time periods and repetition cycles set in the assigned communication devices, - path reservation requests for data streams are classified according to specified access time periods and repetition cycles, wherein the path reservation requests are initiated by a tenant, a user and/or an application in each case, - potential partitions for the path reservation requests are determined on the basis of matching classifications of access time periods and repetition cycles, - the determined partitions are checked to ascertain whether there are sufficient system resources available for the respective path reservation request, - if the result of the check is positive, the respective path reservation request is assigned to at least one determined partition, and system resources required for the path reservation request are reserved within this partition. - at least one control unit (101, 102) controls functions of a plurality of assigned communication devices, and is assigned to at least one partition of the communication network, wherein partitions each comprise specifiable portions of system resources of assigned communication devices for specifiable resource utilization periods, - the communication devices each comprise at least one transceiver, and each transceiver is respectively assigned a plurality of transmit queues, each of which is granted access to the respective transceiver for a definable access time period within a definable repetition cycle, wherein the access time periods and repetition cycles for the transmit queues of the communication devices are controlled by means of a time aware shaper according to IEE 802.1Qbv; wherein, by means of the control unit (101, 102), - the access time periods and repetition cycles for the transmit queues are set in the assigned communication devices by the control unit (101, 102) according to the resource utilization periods for the partitions, - the partitions are classified according to the access time periods and repetition cycles set in the assigned communication devices, - path reservation requests for data streams are classified according to specified access time periods and repetition cycles, wherein the path reservation requests are initiated by a tenant, a user and/or an application in each case, - potential partitions for the path reservation requests are determined on the basis of matching classifications of access time periods and repetition cycles, - the determined partitions are checked to ascertain whether there are sufficient system resources available for the respective path reservation request, - if the result of the check is positive, the respective path reservation request is assigned to at least one determined partition, and system resources required for the path reservation request are reserved within this partition.