## 1 Introduction  
V2X (Vehicle-to-Everything) technology has long been discussed as a key element of autonomous mobility. It is anticipated that by end of the 2020s, all new commercial vehicles will be equipped with the technology to aid automated driving and assistance functions, improving mobility, safety and comfort [1, 2]. The importance of this domain has been demonstrated in numerous technical reviews [3, 4, 5, 6]. This trend has only been accelerated by the global demand during the COVID-19 pandemic [7], and further fuelled by the need for sustainable and ethical technologies [8, 9].  
Nevertheless, few articles dealt with the regulatory and standards aspects. It is believed that 5G, 6G and such technologies will empower most notably the new, autonomous system development in the domain of self-driving systems and telesurgery robots [10]. On the contrary to the common belief that V2X technology itself would enable vehicles for highly automated operation, the automotive community considers this technology as a safety-redundant component of automated driving systems [11]. Considering the ability of the vehicles to communicate with the environment as an extra set of sensors, all automotive development processes and the respective domains of operation are subject to the capabilities and limitations of V2X technology, as well as its integration with other sensors and components of the automated driving systems.  
The safety integrity of automotive systems, including automated driving functions, is uniformly assessed by the ISO 26262 standard, defining their Automotive Safety Integrity Levels (ASIL) [12]. Based on the hazard analysis on severity, exposure and controllability, each component is assessed regarding to its contribution to the whole system. Highlyautomated systems require high ASIL integrity, where the information from V2X communication may be crucial to ensure coherence and redundancy in the system to increase road safety. Vehicles that are produced as of 2024 are not relying on V2X communication alone to contribute to driving functions, as this information is rather used to warn drivers or optimize global route planning. However, with the correct assessment of V2X technology capabilities mapped to the widely accepted Level of Autonomy (LoA), this type of sensory information may become integral part of environmental modeling, decision making and actuation in automated driving systems [13].  
This article aims to systematically assess the requirements towards V2X input data to highly automated and autonomous systems that can individually or in combination with other sensors enable certain LoAs, defined by the Society of Automotive Engineers (SAE) International. The authors discuss regulatory challenges and the issue of scalability in the hybrid environments, where both V2X-capable and traditional vehicles are present on the roads, and map the V2X capabilities to the SAE levels of autonomy by taking into account the features that various protocols provide. A method is proposed for assessing the applicability of V2X at various levels of automation based on system complexity, and an example of the use of the method is provided on one of the common high level automation use-cases. This article is concluded with an outlook to non-automotive technical fields, where V2X-equivalent, IoT-based information is available, and may affect the operation of the automated systems.