 it is responsible for the provisioning of V2X policy and parameter configuration over the PC5 (in- and out-of-coverage) and the LTE-Uu interfaces. The V2X application server (AS) has a wide range of function- alities including the reception of uplink unicast data from the VUEs, VRUs, and RSUs, and the delivery of data to the VUEs in a target area using unicast and/or multicast interfaces. 13.3.2 C-V2X Toward 5G 3GPP is enhancing C-V2X in several ways toward 5G specifications, for what concerns both the radio interface and the architectural functionalities. 13.3.2.1 Radio Interface New radio (NR) V2X specifications in Release 16 (3GPP TR 38.885, 2019) are expected by early 2020 to align C-V2X connectivity with the NR standardization launched, indepen- dently of V2X, for the first phase of 5G in Release 15. The envisioned modifications are 13 5G Network Slicing for V2X Communications: Technologies and Enablers meant (i) to introduce more disruptive technologies such as new/flexible waveforms and numerologies and a larger (mmWave) spectrum to support the most challenging V2X appli- cations' demands (ultralow latency and ultrahigh reliability), and (ii) to improve modes 3 and 4 in order to support peculiar V2X traffic patterns, such as asynchronous traffic, uni- cast/multicast/groupcast, as discussed in [6]. 13.3.2.2 Core Network As the 5G CN design is progressing in 3GPP Release 16, it is under discussion whether a V2X architecture, simpler than the one conceived in Release 14, can be developed by using some of the available features without any component from the EPS. The 5G CN architec- ture is natively designed with modularization and softwarization in mind; it is composed of network functions (NFs) and reference points connecting them. In the 5G architecture, the UE is connected to either the radio access network (RAN) or a non-3GPP access network (AN) such as Wi-Fi², as well as with the Access and Mobility Management Function (AMF). The RAN represents a base station using new radio access technologies (RATs) a