# Video Streaming in Urban Vehicular Environments: Junction-Aware Multipath Approach
## 2 Related Literature
### Street-Oriented Vehicle Selection  
The normal street-oriented video data forwarding in vehicular communication is discussed considering the different existing work that do not consider the junction area during video forwarding. For example, in [PERSON], et al. [30], a Collaborative Video Retrieval (CoRe) scheme has been proposed in order to address the issue of a bandwidth-constrained cellular network, which affects the quality of a video transmitted by a vehicle. The CoRe scheme enables vehicles to transfer quality video from the Internet and distribute it among other vehicles; that is, neighbor vehicles that reside in a normal street during data forwarding. The collaborating vehicles are selected by taking advantage of their on-road characteristics. These on-road characteristics include their obtainable cellular bandwidth, relative velocity, connection period and Euclidean distance. In addition, the neighbor vehicles, which are the collaborating vehicles, download the video stream via the cellular link and disseminate it to a requesting vehicle based on the Dedicated Short-Range Radio Communication (DSRC) protocol. However, only on-road characteristics have been considered; the junctions' characteristics have not been explored. Further, a Multiple Unicast Path-Forwarding (MUPF) scheme has been proposed to tackle the challenges of the traditional IP-based communication in the vehicular network. The scheme explored Information-Centric Networking (ICN) and numerous unicast forwarding paths for data packet forwarding. In addition, the selection of the routing paths considers the issue of link breakage and link quality in relation to the mean response time. However, the situation in which the forwarding vehicle is in the junction area has not been explored. A cooperating neighbor vehicle solution based on the Game-Theory approach for Platoon-centric (GT4P) driving has been suggested to address the challenges of the short contact time among vehicles during multimedia data transmission, which could lead to delay and video packet error [31]. Thus, the video packet error decreases the Quality of Experience (QoE) of the disseminated video. Therefore, a set of neighbor vehicles, which are navigating in the same direction and are willing to collaborate, forms a platoon member that serves as a forwarding vehicle. The GT4P approach improves collaboration among neighbor vehicles by giving a reward to participating vehicles in the platoon. The collaborating platoon members are formed by considering link quality, travel path and mobility parameters including direction, distance, and speed, which minimizes the effect of vehicle mobility on the video streaming transmission. However, the platoon members at different points in the junction area are not considered. Thus, there is a need to explore the junction characteristics. Similarly, a comparative analysis for platoon-centric video streaming transmission in autonomous VANETs has been suggested to assess and ascertain the Quality of Experience (QoE) for shared video flows [32]. Different vehicle distances between the source and destination vehicle and various video characteristics are employed. Thus, the effectiveness of the platoon-centric video transmission is justified considering different video metrics. Further, platoon-centric driving offers a collaborative navigation arrangement for a set of vehicles with the same navigation route such that the member vehicles in the platoon keep almost a fixed distance among themselves. In a typical platoon approach, the cruise control system utilizes the onboard sensors--for example, laser or radar--to estimate the distance between vehicles and then adjust their speed. Further, a member vehicle obtains information from the platoon leader via vehicle-to-vehicle communication. Thus, collision is minimized through communication with vehicles ahead. The platoon approach alleviates the effect of the short contact time that leads to video packet loss or error in the time of video transmission.