Evaluation of Optical Transport Unit Line-Card Integration in Spatially and Spectrally Flexible Optical Networks in Terms of Device Cost and Network Performance

The explosive growth of internet traffic has accelerated the evolution of optical transport networks, emphasizing the need to expand transmission capacity. To overcome the limitations of conventional single-core/mode fiber-based optical transmission, spatial-division multiplexing (SDM) has been proposed. Spatial and spectral superchannel (Spa & Spe SpCh) technology in SDM-based optical networks realizes high-capacity transmission. Such an optical transmission technology can be supported by the Spa & Spe SpCh transceiver and the reconfigurable optical add/drop multiplexer (ROADM), allocating optical carriers (OCs) in spatial and spectral domains simultaneously. The architectures of the manufactured transceivers and ROADMs installed in advance at each network node are fixed. This necessitates the determination of the appropriate spatial and spectral granularity combination that affects the transceiver and ROADM designs to efficiently utilize the switching capacity and reduce the implementation costs. In this paper, we focus on the performance analysis for the
$N$
-core MCF-based network deployment issues under different granularity combinations. Detailed evaluation of a 4-core MCF-based network reveals that the device cost and network performance are influenced by spatial and spectral granularities and can provide guidance for real-world network planning and design. In particular, the trade-off between device cost and network performance based on different granularities should be taken into account in network design.