Patent ID: 7450851
Filing Date: 2008-11-11
Classification: H04J

Abstract:
1. A node for an optical network, comprising: a plurality of in-line switches connected to an optical ring and operable in a first state to both pass an optical signal received from the optical ring to an associated coupler and pass an optical signal received from the associated coupler to the optical ring, the optical signal carrying traffic in a plurality of channels; a drop coupler coupled to a first in-line switch and operable to receive an optical signal from the in-line switch where the switch is in the first state, pass a first copy of the optical signal back to the in-line switch for passing to the optical ring, and drop a second copy of the optical signal to a distributing element; the distributing element operable to receive the second copy and pass traffic in one or more channels of the second copy; a filter operable to receive the first copy via the optical ring from the first in-line switch and to reject one or more channels of the first copy to generate a passthrough signal; a combining element operable to receive traffic in one or more channels to be added to the optical ring and to combine the received traffic to generate an add signal; and an add coupler coupled to a second in-line switch and operable to receive the passthrough signal from the second in-line switch when the switch is in the first state, add the add signal to the passthrough signal to generate a combined signal, and pass the combined signal to the second in-line switch for passing to the optical ring.