# QoS Aware and Fault Tolerance Based Software-Defined Vehicular Networks Using Cloud-Fog Computing
## 2 Literature Review
### SDVN-Based Models
\begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Model Design** & **Model Name** & **Model Structure** & **Advantages** & **Disadvantages** \\ \hline \multirow{4}{*}{VANET Models} & \multirow{4}{*}{VANET Based Mobile Ad-hoc Network} & Vehicular ad-hoc systems for vehicles using wireless technology using mobile cellular system for communication & Efficient for movable vehicles for sharing important information & Dynamic topology updating and connection was a problem \\  & & Safety and Non-Safety Messages VANET Architecture & Priority basis vehicular ad-hoc network for the vehicle to VANETV communication & An efficient model for important messages by non-safety meos/messages \\ \hline \multirow{4}{*}{VANET Models} & \multirow{4}{*}{Open Flow Model} & Software Defined Networking Based V2V & Efficient for cross layer devices and compatible with different machines & Complex, difficult to implement in real world \\  & & Model using wireless technology & Efficient with different machines & \\ \cline{2-5}  & & SNN Based Model & The communication can be delivered to & Difficult to find shortest RSU for multiple vehicles \\ \cline{2-5}  & & Network Architecture & multiple vehicles at a time time & \\ \cline{2-5}  & & Services provision to vehicles to their nearby edge architecture & Reduced response time and energy & Node energy is the problem of edge services \\ \cline{2-5}  & & RTSAR Algorithm & QoS aware model for V2V communication & Reduced connectivity and response time & Point to Point link is a drawback of the system \\ \hline \multirow{4}{*}{SDVN Models for Vehicles Communication} & \multirow{4}{*}{Topology based SDVN Model} & SDN and VANET based model using dynamic path selection of vehicles & Reduced communication cost using uncast and multi-cast models & Difficult to combine SDV with VANET \\  & & Contraster based SDVN Model & Dynamic Controller based V2V model & Efficient for roadside traffic traffic & Controller location placement is dependent on the performance of the model \\ \cline{2-5}  & & Multi-Access Edge Model & Put services on different edges of the network as the network has low latency & Efficient for important messages as the network has low latency & Putting edge devices on different locations is costly \\ \cline{2-5}  & & SDN Environment Based SDVN Model & Open Flow Services based SDVN model & Accommodate one vehicles at a time using switches & Complex architecture and experience more delay \\ \hline \multirow{4}{*}{SDVN Scheduling Models} & \multirow{4}{*}{UVN Based Model} & \multirow{4}{*}{Open Flow Model} & Unmanned Aerial Network, architecture has model, using zone-based data offloading model & \multirow{4}{*}{Efficient for emergency zone data} & Other than emergency zone data will have to experience unlimited delay \\  & & & & \\ \cline{2-5}  & & FCFS, SF based model for urgent, least urgent data & & & \\ \cline{2-5}  & & Priority based model based on deadline and size & & & \\ \cline{2-5}  & & & Priority based model based on deadline and massages & & \\ \cline{2-5}  & & & User different scheduling models for priority-based messages & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Literature review models with comparison.