Digital light distribution system, capacity scheduling method and device

The invention relates to a digital light distribution system and a capacity scheduling method and device. The digital light distribution system comprises a capacity access and routing unit, a capacityexpansion unit and capacity remote units; the capacity expansion unit comprises primary capacity expansion units and cascade capacity expansion units; the capacity access and routing unit is accessedto a core network through a set number of Ethernet interfaces, and the capacity access and routing unit is also connected with a set number of primary capacity expansion units through different routes; each primary capacity expansion unit is in cascade connection with a plurality of cascade capacity expansion units; and the primary capacity expansion units and the cascade capacity expansion unitsare respectively connected with a plurality of capacity remote units. The embodiment of the invention solves the defect that the traditional network coverage scheme cannot flexibly distribute the capacity according to the scen