###### Abstract
Consequently, these approaches cannot be adapted as a solution to the problem at hand because their algorithms are not tailored to the specific requirements of a PON network as they are designed for multiple sources. Moreover, these approaches encompass different physical infrastructures that the same service provider does not invariably control. Thus, their application may be accompanied by elevated implementation costs when implemented in real-world scenarios [17]. Another strategy to optimize the optical spectrum involves the utilization of spatial division multiplexing (SDM) within multi-core fibers. This approach aims to enhance the spectral efficiency by capitalizing on the multiple channels inherent to this fiber type. Furthermore, this methodology employs a self-organizing feature mapping (SOFM) neural network to discern potential crosstalk interference among the channels, thereby mitigating the blocking probability. This conceptual framework facilitates the allocation of dedicated channels for data transmission. Despite its commendable benefits in augmenting data capacity, this inventive approach encounters constraints rooted in its reliance on multi-core fibers. These fibers are constrained by limitations concerning transmission distances. Additionally, they introduce intricacies in configuring PON networks due to their inadequate compatibility and the requisite devices for implementation. Consequently, this circumstance creates substantial costs in system deployment. Furthermore, the efficacy of this approach is contingent upon the availability of optical sources, constituting a significant limitation in furnishing each fiber core [18]. To address the challenges posed by spectrum allocation and the need to create a lower-cost approach, researchers have proposed heuristic methods that utilize multiple modulation formats and reduce the WDM grid spacing to 12.5 and 6.25 GHz values. These approaches, collectively called Routing, Modulation Level, and Spectrum Assignment (RMLSA), are crucial in establishing a flexible optical network to maximize spectral efficiency [19; 20; 21]. RMLSA approaches employ multi-level modulation formats such as QAM, PSK, and QPSK to adjust the modulation level and type to accommodate requests adaptively, thus reducing the required spectrum and complying with the distance constraints of different network requests [13; 22; 23]. Recent research has adopted genetic algorithms to find an optimal solution to the RMLSA problem. This approach simultaneously considers the routing and permutation of requests to explore a more significant portion of the RMLSA solution set than current metaheuristics. Although these approaches offer highly efficient solutions, their computational cost is high, challenging their feasibility in a real operating environment [24]. The RMLSA strategy enables an increase in simultaneous requests, but the economic costs of adding wavelengths constrain its potential. A practical solution to increase the number of wavelengths without significantly escalating costs is the utilization of optical frequency combs (OFCs). An OFC is an optical source with a spectrum composed of a series of discrete frequency lines that are equally spaced and highly coherent [25; 26; 27]. The described properties indicate its potential as a solution for the generation of OFCs. As of 2023, WDM communication systems with speeds approaching 1.84 Pbit/s have been achieved using up to 37 wavelengths [28; 29; 30]. Different techniques for the generation of OFCs have been proposed, such as electro-optic modulation, acousto-optic modulation, ring recirculating modulation, Mach-Zehnder modulators with microresonators, and four-wave mixing. While many of these techniques can achieve comb generation, they carry high economic costs and present considerable insertion losses [31; 32; 33]. The use of micro-resonators (MRR) in integrated photonics has shown great potential in generating optical frequency combs (OFCs) with multiple wavelengths.