Wireless communications are being used for enhancing transport systems .In order to achieve these goals, some communication technologies are specially designed to support Vehicle-to-everything (V2X) functionalities. C-V2X (Cellular Vehicle-to-everything) or LTE-V2X and ITS-G5 are one of the existing solutions respectively standardized by 3GPP (3rd Generation Partnership Project) and ETSI (European Telecommunications Standards Institute). While ITS-G5 is a dedicated wireless network for C-ITS applications, LTE-V2X shares the network resources with other LTE applications used on mobile devices. In this paper, we give an insight on both technologies by briefly describing their communication mechanisms. Then, we compare their performances under different use cases using a networking and vehicular simulation platform. Results show that ITS-G5 outperforms LTE-V2X (mode 3) in case of the presence of concurrent LTE data traffic with V2X service. Throughout the conducted scenarios, we demonstrate the negative impact of handover on LTE-V2X eNB scheduled mode.