## 8 Conclusions and Future Work  
In this article, we have proposed the CAMINO framework, a flexible hybrid V2X connectivity platform for CCAM services. CAMINO is designed to be dynamic, aiming to be the core framework for managing multiple vehicular communication technologies and the services running on top of them. The framework provides integration with existing and future short- and long-range V2X technologies such as ITS-G5, C-V2X PC5 and C-V2X Uu (5G/4G). In addition, it allows integration with vehicle or infrastructure sensors, vehicle actuators, HMIs and third-party service providers. CAMINO can support several standardized, future or custom C-ITS services (e.g., CA, DEN, IVI) that can be triggered dynamically. The corresponding generated messages can be transmitted in a flexible way by one or multiple V2X technologies increasing the transmission capacity or enhancing the transmission reliability. Furthermore, the CAMINO framework is ITS device agnostic, meaning that it can run on top of any type of station such as OBU, RSU, UE, servers, etc. Rich logging capabilities allow the collection of valuable information that enable the performance evaluation of the V2X technologies and the services running on top of them. The flexibility and the modular architecture of the CAMINO framework offer endless research possibilities in the field of vehicular communications and CCAM services. In the near future, we are planning to exploit CAMINO for evaluating the performance of the different V2X technologies available in the Smart Highway testbed. This will allow us to draw valuable conclusions about the real-life performance of the different wireless technologies and identify protocol limitations under various non-deterministic conditions of public streets, where multiple vehicles create dynamic typologies, moving at different speeds and directions during different environmental conditions. The CAMINO framework will also be used to investigate the coexistence of different technologies operating in the 5.9 GHz band based on performance related KPIs such as spectrum occupancy of each technology, packet-loss, latency, etc. This study will give insights into the technology behaviour under mutual interference conditions and will allow to analyse interference solutions in real-life scenarios. Furthermore, Artificial Intelligence (AI) and Machine Learning (ML) techniques will be investigated for autonomous selection of the optimal wireless technology or combination of multiple technologies for transmission and reception of messages from different C-ITS application and services. This selection may take into account several parameters such as the QoS requirements of the application/service (bounded latency, throughput, etc. ), RAN parameters (radio link quality, radio resource utilization parameters), environment conditions (number of neighboring vehicles, distance between them, speed, weather conditions, etc. ), nature of the application (safety/non-safety critical), and more. Figure 7: Packet loss over ITS-G5 between the Belgian vehicle and a Dutch RSU at the Amsterdam pilot site. **Author Contributions:** Conceptualization, D.N., V.M. and S.H. ; Data curation, D.N. and V.M. ; funding acquisition, B.L., J.M.-B. and I.M. ; investigation, D.N., V.M. and I.M. ; methodology, D.N. and V.M. ; project administration, D.N., V.M., S.H., B.L., J.M.-B. and I.M. ; resources, D.N., V.M., S.H., D.v.d.A., S.V., S.M., P.H., J.M.-B. and I.M. ; software, D.N. and V.M. ; supervision, J.M.-B. and I.M. ; validation, D.N. and V.M. ; visualization, D.N. and V.M. ; writing--original draft, D.N. and V.M. ; writing--review and editing, D.N., V.M., S.H., D.v.d.A., S.V., S.M. and I.M. All authors have read and agreed to the published version of the manuscript. **Funding:** The research leading to this article has received funding from the CEF Program under grant agreement INEA/CEF/TRAN/M2016/1364071 (CONCORDA project) and the European H2020 Programs under grant agreement 952189 (5G-BLUEPRINT project), 825496 (5G-MOBIX project), 101016499 (DEDICAT-6G).