## 11 Future Work  
Future work is to implement a test protocol to more precisely define the time-space characteristics for the use of each model to evaluate QoE. Doing this would allow an increased use range of the proposed models. Future work also includes performing a performance validation test of the proposed model and to compare this with the models presented in the \"Related Works\" section in order to analyze the fidelity and performance of the proposed model. At the final part of this research, we did not conduct those performance tests because our work was dedicated to validating the model fidelity using the test protocol proposed by VQEG and correlation tests with SSIM and PSNR.  
To conduct those performance tests, it is necessary to implement a test plan or to have simulation tools to continue feeding the designed database with new videos that contain many distortions rather than only the distortions caused by QoS parameters modification. The database update is important because some databases are outdated or they provide scarce technical information. To present an improved version of the proposed models, we can analyze the performance of the proposed models by comparing the obtained results to PSNR and SSIM, and, based on the results of the last item and aiming to improve the fidelity of the models, we must obtain new video sequences in YUV format, so that encoding does not affect the video quality upon transmission in the testbed.  
In addition to the proposed models, we designed a database as a result of the tests applied to the three proposed models. It contains over 48 videos evaluated subjectively; each video features distortions produced by its transmission in a laboratory environment with three QoS parameters being modified. This database will be online for the research community in a short time. We are also working toward adjusting the spatial-temporal range of each type of video in order to analyze each model performance. This document is focused on the quality metrics of the user experience and service, methodology and mathematical model. The details of the registration and transmission processes of the FANET network are found in an already accepted article and will be published very soon.  
In [55], the alignment of subjective network parameters with network performance is proposed. Establishing a relationship between the conclusions of that work with the results of the research presented here would be enriching.  
A new quality-of-experience-driven rate adaptation approach for adaptive HTTP streaming was presented in [56]. Their research was conducted in wireless network environments and demonstrated that the proposed mechanism could maximize QoS, particularly when the performance was variable. That document was focused on the quality metrics of the user experience and service, methodology and mathematical model. The details of the registration and transmission processes of the FANET network are found in an already accepted article and will be published soon.  
Project administration, J.H.O.M.; Investigation and writing--original draft, J.L.A.H.; Investigation and Formal analysis J.C.C.Q.; Supervision and writing--review and editing C.A.T.R.; Conceptualization and Methodology B.T.A. All authors have read and agreed to the published version of the manuscript.  
This work benefited from the support of the Telematics Engineering Group of the University of Cauca. This paper shows part of results of the project \"Framework for deployment and management of video content--Phase I\" ID 4977. We are especially grateful to The VRI of University of Cauca for its financial support.  
Not applicable.  
The data that support the findings of this study are available from the corresponding author upon reasonable request.  
The authors declare that they have no conflict of interest to report regarding the present study.