Optical subchannel routing, protection switching and security

摘要

The present invention includes novel techniques, apparatus, and systems for optical WDM communications. Tunable lasers are employed to generate subcarrier frequencies representing subchannels of an ITU channel to which client signals can be mapped. Client circuits can be divided and combined before being mapped, independent of one another, to individual subchannels within and across ITU channels. Subchannels may be independently routed to a single subchannel receiver filter, such that each subchannel detected at the receiver may come from a different source location. Network architectures and subchannel transponders, muxponders and crossponders are disclosed, and techniques are employed (at the subchannel level/layer), to facilitate the desired optical routing, switching, concatenation and protection of client circuits mapped to these subchannels across the nodes of a WDM network. Subchannel hopping may also be used to increase the optical network security.

主权项

1. A system that can route client signals among a plurality of nodes interconnected by one or more fiber optic cables to form an optical network, the system comprising:
a subchannel mapper that can map each of a plurality of client signals to a corresponding subchannel within or across a plurality of ITU channels, wherein each ITU channel in the plurality of ITU channels has a predefined ITU frequency and a corresponding plurality of subchannels, and wherein each subchannel has an associated frequency with a predetermined offset from the predefined ITU frequency of the subchannel's corresponding ITU channel; a first network route that designates the origin of a first client signal at a first node, and a destination for the first client signal at a second node; and a tunable laser at the first node that can be set to a first subchannel frequency for which the second node has a filter to receive signals transmitted at that subchannel frequency, whereby the system can route the client signal from the first node to the second node by tuning the laser to the first subchannel frequency and mapping the client signal to the subchannel associated with that subchannel frequency.