## 1 Introduction
Such integration is presented in Figure 2. In this case, the functional duties performed by RSU base stations are assigned to a constellation of low-orbit satellites. In expanding road safety capabilities, satellite Internet of Vehicles technology requires addressing a number of important challenges. One of them is ensuring the cybersecurity of satellite IoV. This is due to the fact that the communication channel is long, resulting in new vulnerabilities in the IoV system. This contributes to the emergence of new types of cyberattacks on the low-orbit satellite communication system, the execution of which leads to significant economic losses. In [15; 16], the vulnerabilities of modern satellite systems to cyberattacks are discussed. The authors described the main problems of the cybersecurity of space systems. They considered the main types of cyberattacks that have been executed on satellites by hackers, as well as methods aimed at reducing damage to the assets of satellite systems. The analysis of these works allowed us to divide the multitude of executed cyberattacks into three main groups. The first group includes a direct attack on a satellite. It can be performed either through a ground-based transceiver or via a satellite. The second group includes attacks on the satellite system through a ground control point that can be compromised by hackers. The third group includes attacks that are built on delivering malicious code to a satellite via an officially provided access channel. These cyberattacks are not only capable of disabling satellite communication system assets but also of disrupting the data link. To effectively counter such cyberattacks, it is necessary to develop and utilize a set of best practices and techniques that can ensure the cybersecurity of satellite IoV. It is known that cybersecurity includes identification and authentication methods, algorithms used for data traceability and authorization, the application of which is aimed at ensuring the integrity, availability and confidentiality of information. The paper proposes a new approach to improving the cybersecurity of the satellite IoV through the use of the developed authentication protocol that allows for granting access rights only to those elements of the satellite IoV structure that have confirmed their legitimacy. This approach is based on the integration of zero-knowledge authentication protocols (ZKAP) and methods of constructing noise-resistant modular codes. One of the effective cyberattacks conducted on satellite IoV assets is the spoofing attack, which is presented in Figure 3. The satellite RSU transmits true content to the vehicle OBU  
Figure 2: Satellite IoV. (shown in yellow). A rogue satellite intercepts this message, delays the content, and then imposes it on the OBU (this process is shown in red). In this case, the received spoofing interference will be perceived by the OBU as correct information about the current traffic condition and will be accepted for execution. As a result, traffic safety will be impaired. In addition, a rogue satellite can intercept the communication channel when the handoff (handover) procedure is being performed. Since the time when a low-orbit satellite is in the receiver's line of sight is between 8 and 15 min, the handoff process must be performed from one satellite to another satellite during the handoff session to ensure uninterrupted data exchange between the OBU and the satellite RSU. A rogue satellite can intercept the communication channel and transmit unauthorized content containing false traffic information to the OBU exactly during the handoff procedure. As a result, road safety will also be compromised. It is proposed to counter such a cyberattack by using a zero-knowledge authentication protocol based on a modular polyalphabetic polynomial code (MPPC).