On the trade-off between maximizing spectral efficiency and minimizing capacity overprovisioning in DWDM networks

Abstract

The adoption of a flexible dense wavelength division multiplexed (DWDM) grid in optical transport networks will materialize the envisioned opportunity to capitalize from a more efficient spectrum allocation. Particularly, routing media channels comprising multiple adjacent carriers enables to pack them closer together and use a single pair of guard bands of adaptive size to accommodate filtering impairments. However, fully exploiting this flexibility can result in a wide array of media channel configurations, increasing the complexity of planning and operating the network. Moreover, there is a potential capacity mismatch between the actual traffic requirements between two nodes and the most spectrally efficient media channel configuration that can be deployed between those nodes. This paper provides insight on how the set of media channels supported in a flexi-grid DWDM network impacts the network spectral efficiency and assesses the trade-off between maximizing spectral efficiency and minimizing capacity overprovisioning.