# Intelligence-Based Strategies with Vehicle-to-Everything Network: A Review
## 2 Background
### V2X Technologies  
A proliferation of interconnected and fully autonomous vehicles on the roads is causing significant innovations in the transportation and automotive sectors, resulting in improved reliability and safety. There are two powerful technologies of VANETs for V2X, i.e., Dedicated Short-range Communication (DSRC) and Long-Term Evolution (LTE)-based technology [18]. The very initial design of the V2X was constructed by utilizing dedicated DSRC and the IEEE 802.11p network protocol [3; 19]. The DSRC protocol is a \"full duplex wireless network facility, enabling highly rapid data transfer rates crucial to communications-based security programs\", as the U.S. Department of Transportation defines it. In 1999, the Federal Communications Commission designated 75 MHz of spectrum within the 5.9 GHz band (5.850-5.925 GHz) to implement vehicle security and transportation services. It is an open-source wireless communication protocol with certain resemblances to WiFi, designed to facilitate ITS applications (V2V and V2I), fast speeds, and secured and short-range communication among vehicles and infrastructure. Enhancing the whole transportation experience, reducing traffic jams, and improving traffic safety are the primary objectives of DSRC. V2V communication via VANET is free of infrastructure, which is crucial to guarantee security among underdeveloped and faraway places, particularly on misty roads. Common Awareness Messages (CAMs) and Basic Safety Messages (BSMs) can be transmitted by automobiles in DSRC at less than 100 milliseconds. DSRC, a minor alteration of the IEEE 802.11 protocol, facilitates the deployment of VANETs. The Medium Access Control (MAC) protocol of DSRC is based on Carrier-Sense Multiple Access/Collision Avoidance (CSMA/CA), which can result in unrestricted delays and stability [20], despite the fact that VANET nodes can connect to the internet rapidly. The invention of the DSRC protocol from the year 1999 to 2020 is presented in Figure 3. After the year 2020, it will be upgraded with IEEE 802.11 bd to enhance the performance at a higher speed. In contrast, the LTE specification is widely implemented as a fundamental aspect of 5G technology and is presently undergoing further development as 4G broadband wireless technology [19]. LTE is characterized by its exceptional dependability, expanded bandwidth, and the necessity for pre-deployment alterations in the V2X system [3; 21]. Vehicular-to-everything communication, which facilitates collaboration between cars, will enhance situational consciousness and perception of roadside infrastructures, pedestrians, and other road elements in this particular environment. Cellular-vehicle-to-everything (C-V2X) [12] is becoming increasingly popular for connecting and automating vehicles in the coming years, particularly for sidelink LTE-V2X Mode 4. It uses a PC5 interface in the 5.9 GHz band to transmit and receive messages for vehicular ad hoc networks. Two powerful technologies of cellular-V2X communication that come under the umbrella that is used for V2X are LTE-V2X and 5G-V2X. The physical connectivity of LTE, called sidelink, has been released by the most recent 3 rd Generation Partnership Project (3 GPP) standards for LTE V2X. This differs from the conventional uplink and downlink network traffic of LTE. The LTE V2X is capable of operating in two distinct modes via sidelink: first, LTE-V-Cell mode, for long-range (wide-area) communications that employ the mobile network for direct radio transmission between the C (UE) and the Base Station, called eNodeB (eNB); second, LTE-V-Direct mode, which employs sidelink as the physical link [22] by employing independent Time Division Multiple Access (TDMA), as Medium Access Control (MAC), in which the duration is partitioned into segments. Before entering the connection, the communication devices must connect to the link by arbitrarily selecting an unoccupied slot after initially listening to the carrier to collect packet information.