A network arrangement for aggregation of groups of tunable sources in a
photonic network is disclosed. The network arrangement includes transmit
edge elements having a plurality of tunable optical transmitters, an
optical switch and a cyclic optical multiplexer, and receive edge
elements having optical demultiplexers, optical switches and a plurality
of optical receivers. A variety of arrangements are disclosed including
protected and unprotected network architectures. The network arrangement
disclosed is particularly useful for overcoming the problem of scaling a
photonic network.