An optical network includes an optical ring and at least three subnets.
Each subnet includes a plurality of add/drop nodes coupled to the optical
ring. The add/drop nodes are operable to passively add a first traffic
stream in a first direction on the optical ring and a second traffic
stream in a second direction on the optical ring. The first traffic
stream comprises different content than the second traffic stream, and
the first traffic stream and the second traffic stream are transmitted on
the same wavelength. The network also includes a plurality of gateway
nodes. The gateway nodes are each coupled to the optical ring at a
boundary between neighboring subnets and are operable to selectively pass
and terminate wavelengths between subnets to allow wavelength reuse in
the subnets.