# V2X Communication over Cellular Networks: Capabilities and Challenges
## 3 3 GPP's V2X Architecture
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**UC \#**} & \multirow{2}{*}{**Title**} & \multicolumn{2}{c}{**Delay**} & \multicolumn{2}{c}{**Reliability**} & \multicolumn{2}{c}{**Throughput**} \\ \cline{3-8}  & & **5 GAA** & **3 GPP** & **5 GAA** & **3 GPP** & **5 GAA** & **3 GPP** \\ \hline \multirow{2}{*}{**1**} & \multirow{2}{*}{Platooning} & Delay & \multirow{2}{*}{10–25 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{90\%} & \multirow{2}{*}{8–48 kbps} & \multirow{2}{*}{-} \\  & & Sensitive & & & & & \\ \hline \multirow{2}{*}{**2**} & Sensor and State Map & \multirow{2}{*}{-} & \multirow{2}{*}{10 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{90\%} & \multirow{2}{*}{4–47 Mbps} & \multirow{2}{*}{25 Mbps} \\  & Sharing & & & & & & \\ \multirow{2}{*}{**3**} & Remote Driving & Delay & \multirow{2}{*}{5 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{400 kbps–36 Mbps} & \multirow{2}{*}{1–20 Mbps} \\  & Sensitive & & & & & \\ \multirow{2}{*}{**4**} & LaneChange & \multirow{2}{*}{-} & \multirow{2}{*}{10–25 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{90–99.99\%} & \multirow{2}{*}{120 kbps} & \multirow{2}{*}{-} \\  & Infrastructure-based & & & & & \\ \multirow{2}{*}{**5**} & Perception of & \multirow{2}{*}{-} & \multirow{2}{*}{3–100 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{99.999\%} & \multirow{2}{*}{4–155 Mbps} & \multirow{2}{*}{1 Gbps} \\  & Environment & & & & & \\ \multirow{2}{*}{**6**} & Collision Avoidance & \multirow{2}{*}{-} & \multirow{2}{*}{\(<\)10 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{99.99\%} & \multirow{2}{*}{10 Mbps} & \multirow{2}{*}{-} \\ \multirow{2}{*}{**7**} & Collective Information & \multirow{2}{*}{10 ms} & \multirow{2}{*}{100 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{High} & \multirow{2}{*}{120 kbps} & \multirow{2}{*}{50 Mbps} \\  & Sharing & & & & & & \\ \multirow{2}{*}{**8**} & See Through for & \multirow{2}{*}{50 ms} & \multirow{2}{*}{10–50 ms} & \multirow{2}{*}{99\%} & \multirow{2}{*}{90–99.99\%} & \multirow{2}{*}{8 Mbps} & \multirow{2}{*}{10–70 Mbps} \\  & Passing & & & & & & \\ \multirow{2}{*}{**9**} & Emergency Trajectory & \multirow{2}{*}{-} & \multirow{2}{*}{3 ms} & \multirow{2}{*}{-} & \multirow{2}{*}{99.99\%} & \multirow{2}{*}{48 kbps} & \multirow{2}{*}{30 Mbps} \\  & Alignment & & & & & & \\ \multirow{2}{*}{**10**} & Intersection Crossing & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{8–25 kbps} & \multirow{2}{*}{50 Mbps} \\ \hline \multirow{2}{*}{**11**} & Cooperative Driving & - & \(<\)5 ms & - & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: V2X use case requirements. The Access and Mobility management Function (AMF) handles mobility management and obtains V2X subscription information from the Unified Data Management (UDM). Additionally, it retrieves PC5 QoS information from the PCF, and provides the aforementioned parameters to the NG Radio Access Network (NG-RAN);  
The V2X AS provides V2X parameters to the UE and the 5G core network. It receives UL data and sends DL data from/to the UE over unicast. Furthermore, it may request to receive notifications about potential QoS modifications in a specific geographic area. This information may be received through the Network Exposure Function (NEF). In relation to the PC5 reference point, which relates to direct communication among the UEs, it is considered for V2X communication by both LTE and 5G-NR. In LTE's Mode 3, the network allocates the resources to be used by the UEs. In Mode 4, the UEs autonomously select the resources to use for direct communication [25]. For LTE, the broadcast mode is the only supported communication mode. In 5G-NR, the respective communication modes are Mode 1 and Mode 2, which are enhanced compared to those of LTE, in order to improve the efficiency and provide QoS for the UEs. Additionally, broadcast, multicast, and unicast modes can be supported over the PC5 interface [23]. Regarding the 5G Uu interface, multicast and broadcast communication types have not yet been specified.