Abstract: An example system includes a hub transceiver and a plurality of edge transceivers. The hub transceiver is operable to transmit, over a first communications channel, a first message to each of the edge transceivers concurrently, including an indication of available network resources on an optical communications network. The message may be transmitted through amplitude modulation of a plurality of optical subcarriers output from the hub. Each of the edge transceiver is operable to transmit, over a second communications channel, such as a subcarrier having a reduced spectral width and/or power than optical subcarriers carrying user data. The second communications channel carries a respective second message to the hub transceiver including an indication of a respective subset of the available network resources selected by the edge transceiver for use in communicating over the optical communications network.