###### Abstract  
In the upcoming decade and beyond, the Cooperative, Connected and Automated Mobility (CCAM) initiative will play a huge role in increasing road safety, traffic efficiency and comfort of driving in Europe. While several individual vehicular wireless communication technologies exist, there is still a lack of real flexible and modular platforms that can support the need for hybrid communication. In this paper, we propose a novel vehicular communication management framework (CAMINO), which incorporates flexible support for both short-range direct and long-range cellular technologies and offers built-in Cooperative Intelligent Transport Systems' (C-ITS) services for experimental validation in real-life settings. Moreover, integration with vehicle and infrastructure sensors/actuators and external services is enabled using a Distributed Uniform Streaming (DUST) framework. The framework is implemented and evaluated in the Smart Highway test site for two targeted use cases, proofing the functional operation in realistic environments. The flexibility and the modular architecture of the hybrid CAMINO framework offers valuable research potential in the field of vehicular communications and CCAM services and can enable cross-technology vehicular connectivity. 25 February 202120 March 202122 March 202125 February 202120 March 2  
U.S., namely ITS-G5 and Dedicated Short Range Communication (DSRC) respectively. The second is the cellular based C-V2X PC5 technology. Furthermore, 4G and especially 5G are seen as the technologies to further drive this CCAM paradigm and provide longer range communication to infrastructure and cloud services [2]. A classification of the different V2X technologies is shown in Figure 1.  
In spring 2019, the European Commission attempted to provide clarity around the technology to be used by automotive Original Equipment Manufacturers (OEMs) by publishing a Delegated Act on Cooperative ITS (C-ITS), based on ITS Directive 2010/40/EU [3]. The Delegated Act aimed to define requirements for C-ITS stations and services, endorsing the ITS-G5 standard as the baseline technology for direct communication between vehicles and infrastructure. However, according to the European spectrum regulations, the 5855-5925 MHz ITS band must be technology neutral. This implies that any radio technology, which can demonstrate conformance with the essential requirements of the Radio Equipment Directive (e.g., through compliance with EN 302 571 [4]) can operate in the ITS band. For this reason, the Delegated Act was rejected by the EU Member States, as being in favor of one technology does not ensure the technology neutrality of the 5.9 GHz ITS band. As a result, each automotive OEM can independently select its favorable short-range communication technology. Today, most car and truck manufacturers hesitate to select and integrate a specific technology, but they keep monitoring the progress happening in both domains so that they can chose the one that potentially dominates in the future. However, some OEMs have already started integrating a specific short-range V2X technology. For example, Volkswagen, one of the best selling OEMs in Europe, has announced that the new Golf 8 will use ITS-G5 for its Car2X technology [5]. On the contrary, other OEMs such as BMW, Audi and Ford focus more on C-V2X PC5 [6]. Today, long- and short-range technologies are typically targeting different use cases where each technology has its own characteristics, advantages and drawbacks that make it more or less capable in addressing the diverse requirements of connected and autonomous driving applications, such as end-to-end latency, throughput, reliability, etc. For instance, short-range technologies (C-V2X PC5 and ITS-G5) are more suitable for serving low latency use cases such as truck platooning, while long-range technologies (4G/5G C-V2X Uu) can provide the necessary throughput for passenger infotainment applications.