## 7 Future Work  
The paper presents proposed solutions that can be used in the design of 5G system components intended for the use in radio domain networks. The calculations and simulations performed show the potential applications of the proposed interfaces. In the next stage of work on the proposed network solutions, extended simulations should be carried out, which will demonstrate the possibility of a correct physical operation of the A-RoF and D-RoF interfaces. It should be noted here that the coexistence of these interfaces in the DWDM/EON link is preferred. Simulations will be conducted in the photonic domain and partly in the radio domain using the VPIphotonics or OptiWave platforms. Having in mind that the operation of digital and analog interfaces is completely different, this will require appropriate selection of simulation parameters due to the way the signal samples are created. In the optical path, linear and nonlinear phenomena should be taken into account. The main components of the network that will bring these distortions will be single-mode telecommunications optical fibers and, to a lesser extent, lasers, external optical modulators, and optical multiplexers. The author declares no conflict of interest. * [PERSON] and [PERSON] (2019) [PERSON]; [PERSON] [PERSON] Experimental OAI-based Testbed for Evaluating the Impact of Different Functional Splits on C-RAN Performance. In Proceedings of the 2019 Novel Intelligent and Leading Emerging Sciences Conference (NILES), Giza, Egypt, 28-30 October 2019. Available online: [[https://ieeexplore.ieee.org/document/8909310](https://ieeexplore.ieee.org/document/8909310)]([https://ieeexplore.ieee.org/document/8909310](https://ieeexplore.ieee.org/document/8909310)) (accessed on 13 January 2020). * [PERSON] et al. (2015) [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON] [PERSON]; [PERSON]; [PERSON] Optimal BBU Placement for 5G C-RAN Deployment Over WDM Aggregation Networks. _J. Lightwave Technol._**2015**, 34, 1963-1970. Available online: [[https://ieeexplore.ieee.org/document/7368094](https://ieeexplore.ieee.org/document/7368094)]([https://ieeexplore.ieee.org/document/7368094](https://ieeexplore.ieee.org/document/7368094)) (accessed on 11 January 2020). [CrossRef]
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