A method includes receiving a schedule of transmission start slots on a network node, the slots representing reserved and/or nonreserved opportunities for initiating data transmission by at least one network device in a network, the reserved opportunities associated with specific network devices, and the non-reserved opportunities available for non-reserved use by any network device on the network, and adjusting the schedule in accordance with successful transmissions by other network nodes. Another method includes generating a schedule of transmission start slots on a master node, where the slots represent reserved and/or nonreserved transmission initiation opportunities for the initiation of data transmission by at least one of a plurality of network devices in a network, the reserved opportunities being associated with specific network nodes, and the nonreserved opportunities being available for nonreserved use by any the network devices on the network, and distributing the schedule to the network devices.