Whether the network application is to increase connectivity between data centers, deliver bandwidth-intensive content, or move business applications into the cloud, the photonic layer provides the mechanism to efficiently light the fiber by assigning wavelength capacity to the optical spectrum. Networks with high bandwidth applications and sustained bandwidth growth are quickly facing capacity exhaust on routes between key locations. Once existing capacity is consumed, lighting additional fiber pairs is required. If the cost of laying or leasing new fiber is too prohibitive, or fiber availability is scarce, then alternatives to unlocking additional capacity are needed. As a result, network operators are increasingly looking at expansion into the L-band to increase fiber capacity.