Patent ID: 7254336

Claim:
A method for seamless migration from a scaleable optical add/drop multiplexer to a network switching node in an optical transport network, comprising: providing a pre-deployed optical add/drop multiplexer (OADM) at a network node in the optical transport network, the pre-deployed OADM configured to support at least two optical transport lines; introducing an added optical add/drop multiplexer (OADM) at the network node, the added OADM configured to support at least two optical transport lines; and interconnecting the pre-deployed OADM to the added OADM using a photonic cross-connect switch, where the photonic cross-connect switch is operable to route optical signals amongst the optical transport lines connected to the pre-deployed OADM and the added OADM; configuring each of the pre-deployed OADM and the added OADM with at least one upgrade inlet port and at least one upgrade outlet port, such that the photonic cross-connect switch is connected via the upgrade inlet ports and the upgrade outlet ports to the pre-deployed OADM and the added OADM; receiving an optical multiplexed signal at a first port of the pre-deployed OADM, the optical multiplexed signal having a plurality of data signals embodied therein; splitting the optical multiplexed signal into a pass-thru multiplexed signal and an outgoing routable multiplexed signal; and routing the outgoing routable multiplexed signal via an upgrade outlet port to the photonic cross-connect switch.