A method for data transmission in a local are network, wherein data is transmitted on the Media Access Control (MAC) layer within successive time frames between a plurality of first nodes comprising client nodes to a second node comprising a coordinator node for the plurality of first nodes. A synchronizing slot for sending a synchronizing message from the second node to the first nodes includes acknowledgements for time slots used for data transmissions in previous time frames from the first nodes to the second node. The acknowledgements indicate whether a data transmission in the previous time frame was successful. Based on these acknowledgements, retransmission time slots included in the current time frame are used for retransmitting data that have not been transmitted successfully in a time slot of the previous time frame.