Patent ID: 8073332

Claim:
A photonic cross-connect, comprising: a first ingress port receiving a first dense wavelength division multiplex (DWDM) signal connected to an input of a first ingress wavelength selective switch (WSS); an egress port connected to an output of a first egress WSS transmitting a second DWDM signal, the first ingress port and the first egress port representing a bidirectional port for exchanging DWDM signals in a first direction, at least a second ingress port receiving a third DWDM signal connected to an input of at least a second ingress WSS and at least a second egress port connected to an output of at least a second egress WSS transmitting a fourth DWDM signal, the second ingress port and the second egress port representing a bidirectional port for exchanging DWDM signals in a second direction, the first and the at least second ingress WSS having at least one through output, each through output being connected to an through input of each other egress WSS transmitting DWDM signals (W 4 , E 2 ) in another direction, the first and the at least second ingress WSS having drop outputs outputting a first WDM drop signal and respectively at least a second WDM drop signal, both WDM drop signals comprising odd or only even channels, the first and the at least second egress WSS having add inputs for receiving a first WDM add signal and at least a second WDM add signal respectively, both WDM add signals comprising odd or only even channels, a drop arrangement with a first and at least a second drop input, connected to drop outputs of the first and at least the second ingress WSS respectively, the drop arrangement combining odd channels or even channels of the WDM drop signals, and with at least one output connected to a drop demultiplexer singularizing the WDM drop signals into client drop signals, an add arrangement with at least one input connected to an output of a multiplexer combining received client add signals, with a first add output and at least a second add output connected to the add inputs of the first egress WSS and the at least second egress WSS respectively, and wherein wavelength selective elements in a drop path and in an add path comply with at least a double frequency spacing and about a double bandwidth of the ingress WS-switches or egress WS-switches.