# Optical Communications and Networking Solutions for the Support of C-RAN in a 5G Environment  
[PERSON]  
1 DIET, University of Roma Sapienza, Via Eudossiana 18, 00184 Roma, Italy; [EMAIL_ADDRESS]  
[PERSON]  
1 DIET, University of Roma Sapienza, Via Eudossiana 18, 00184 Roma, Italy; [EMAIL_ADDRESS]  
[PERSON]  
2 Fondazione Ugo Bordoni, Viale del Policlinico 147, 00161 Roma, Italy; [EMAIL_ADDRESS]  
bandwidth resources according to the current traffic demand. The network topology is composed of OTN/DWDM rings and the objective of the paper is to evaluate the best configuration (number of rings and number of wavelengths needed) to both to minimize the cost and to provide an implementable solution. The authors perform an analytical study and evaluate the advantages of the proposed dynamic resource allocation solution with respect to the static solution in which the network is provided with a number of wavelengths determined in the scenario in which the radio station works at full load. With this approach, the bandwidth saving can reach up to 90% in a 5G traffic scenario. The second paper, authored by [PERSON] et al. and titled \"Traffic Estimation-Based Low-Latency XGS-PON Mobile Fronthaul for Small Cell C-RAN Based on Adaptive Learning Neural Network\" [6], proposes and investigates a solution to guarantee low latency in fronthaul networks realized in Passive Optical Network (PON) technology. The proposed technique is based on the prediction of packets arriving at the Optical Network Unit (ONU) buffer from the Remote Radio Unit (RRU) using an adaptive learning neural network function integrated into the Dynamic Bandwidth Allocation (DBA) module at the optical line terminal (OLT). The performance of the new method is evaluated by means of simulation. The results confirm the capability of the proposed method of achieving the latency requirement for a mobile fronthaul network while outperforming algorithms proposed in the literature for the resource allocation in PON fronthaul networks. The third paper, authored by [PERSON] et al. and titled \"C-RAN Traffic Aggregation on Latency-Controlled Ethernet Links\" [7], proposes and investigates a novel fronthaul network architecture that supports both CPRI traffic with a high time transparency and pre-emptiable backhaul traffic. The objective of the solution is to guarantee a hard delay for fronthaul traffic and at the same time to maximize the backhaul traffic throughput. The introduction of such a solution in a 5G transport network would allow compatibility with the widely deployed ethernet standard while significantly enhancing the scalability and the flexibility of the C-RAN optical infrastructure. The fourth paper, authored by [PERSON] et al. and titled \"A Genetic Algorithm for VNF Provisioning in NFV-Enabled Cloud/MEC RAN Architectures\" [8], proposes and investigates a C-RAN architecture provided with Network Function Virtualization (NFV) and Mobile Edge Computing (MEC) technologies in order to: (i) allow for a flexible processing and RAM resource allocation; (ii) guarantee better Quality of Service thanks to the availability of resources near to the user. The paper addresses the problems of Virtual Network Functions (VNF) provisioning (VNF-placement and service chain allocation) in a 5G network. In order to solve this problem, the authors propose a genetic algorithm that, considering both computing resources and optical network capacity, minimizes both the service blocking rate and processing resources usage. The proposed solution outperforms previous proposals in the literature, reducing the service blocking ratio while saving energy by reducing the number of active processing cores. The fifth paper, authored by [PERSON] and titled \"Analysis of 5G New Radio Uplink Signals on an Analogue-RoF System Based on DSP-Assisted Channel Aggregation\" [9], proposes and compares some solutions for the transmission of signals in 5G radio access technology on an interface referred to as New Radio (NR).