A communications network for a metropolitan area is disclosed. The network
is comprised of three basic types of nodes: an access multiplexer, a
photonic switch, and a core node. The access multiplexer provides
multiplexing of data packets from end-users onto at least one sparse
wavelength division multiplexed (SWDM) wavelength. The SWDM wavelengths
are carried over fiber cable to the photonic switches, which consolidate
these wavelengths into dense wavelength division multiplexed (DWDM)
wavelengths for transmission to the core node. The core nodes include a
photonic switch (PSX) and a service-aware terabit router core for routing
packets within the metropolitan area via the network or out to a long
haul network. The photonic switches and core nodes are capable of
switching at the wavelength, group of wavelength, and fiber levels.