NODE ARCHITECTURES FOR NEXT GENERATION ROADMS: A COMPARATIVE STUDY AMONG EMERGENT OPTICAL SOLUTIONS
Keywords:ROADM, next generation optical network, multicast switch, cross-connect, WSS
Reconfigurable optical add and drop multiplexers (ROADMs) are key components to increase the dynamicity and flexibility of optical networks. In its first generation, solely based on PLC and WSS-technology, ROADMs allowed service providers to automate some of its network operations, reducing the OPEX and improving the quality of service offered to the customer. However, the current solution is limited to several constrains such as direction, color and contention, and still demands truck rolls and manual reconfiguration depending on the desired operation. To address this limitation, new optical components are emerging and particularly two node architectures are being considered as most promising candidates: multicast switch with optical amplification array and dense low loss fiber optical cross-connect with MUX/DEMUX AWGs. This paper compares both solutions, and a third variation using fiber OXC in conjunction with WSS, from a CAPEX and OPEX perspective. It concludes that depending on the network scenario one solution is more suitable than the others and probably, in the next generation reality, different node architectures will be required in different portions of a same network.
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