msc {
    hscale="1.5";
    model[label="Model"],
    access[label="Access reliable module"],
    core[label="Access + Mesh core"];

    |||;
    model note core[label="Send acknowledged message to a unicast address", textbgcolor="#FFB000"];
    |||;
    model => access[label="access_model_reliable_publish(&reliable_config)"];
    access => core[label="timer_sch_scehdule(...)"];
    access =>> access[label="add_to_list(...)"];
    access => core[label="nrf_mesh_packet_send(...)"];
    model << access[label="NRF_SUCCESS"];
    ...;
    access <<= core[label="timer_sch_cb()"];
    access => core[label="nrf_mesh_packet_send(...)"];
    access => core[label="timer_sch_reschedule(...)"];
    ...;
    access <<= core[label="timer_sch_cb()"];
    access => core[label="nrf_mesh_packet_send(...)"];
    access => core[label="timer_sch_reschedule(...)"];
    ...;
    ---[label=" Final timeout "];
    access <<= core[label="timer_sch_cb()"];
    access =>> access[label="remove_from_list(...)"];
    access =>> model[label="timeout_cb()"];
}