## 2 Related Work
### GPS-Location-Based Geocast Routing with Link Quality  
The impact of radio channel propagation, such as noise, fading, shadowing, etc. on one-hop link connection is one of the crucial issues to consider while studying geocast routing in VANETs. An approach for geocasting [24] in VANETs that uses multiple metrics to choose the next-hop vehicle has been proposed by the authors. The suggested technique makes use of metrics that are based on links and vehicle density to search a reliable next forwarding vehicle for message dissemination in the geocast region. Intermittent Geocast Routing (IGR) [25] in urban VDTNs with storage-carry-forward mode. The IGR operates in two modes: intersection mode and road segment mode. In the intersection mode, the network connectivity characteristic is studied to determine the probability of connectedness for any road segment. In the following hop, the maximum connected road stretch is chosen. Then, on the selected road segment, the vehicular nodes estimate the effective connection interval based on the real road and vehicle circumstances.  
To enhance the geographical routing strategy over VANET, a prediction-based geographical routing (PGR) approach is suggested using link quality measure. It reconsidered the forwarding and repair procedures of the routing approach given in [26]. [PERSON] et al. [27] performed an analysis of the precision of the location information of vehicles, which is dependent on the effectiveness and scalability of geographical routing. Through the use of GPS or other positioning technologies, the vehicle is able to control its own location. The geographical routing takes into consideration the precise location information implicitly. However, taking into account the GPS's accuracy limitations and the fact that signals might be blocked by the environments along roadways, this assumption is not reasonable. The erroneous location information is the root cause of the performance issues that occur as a result of using geographical routing methods. Specifically, [PERSON] et al. [28]. demonstrate that inaccuracies in location during geographic routing (in wireless sensor networks) can lead to poor performance or even total failures. In geographic routing, it is necessary for each node to have information regarding its present position, which can be obtained by the use of GPS or another type of localization technique ([PERSON] et al. [29]). In wireless sensor networks, one of the most crucial tasks to complete is the installation of a localization system. As a result of the geographic correlation of the sensed data, location information is frequently used to name the obtained data, address nodes, and regions and also to improve the performance of a wide variety of geographic algorithms. GPS-location-based Link quality and Degree of connectivity based Geographic Distance Routing (SLD-GEDIR) [17] is proposed, selecting the most dependable forwarding vehicle by taking into consideration one-hop link quality.  
Nevertheless, the aforementioned routing approaches do not take into account dynamic vehicles movement patterns while considering one-hop link quality as one of the routing metrics, and these routing approaches are not suitable under a vehicular network scenario with intermittent connectivity under sparse vehicular networks and where GPS outages occur. However, in a VANETs scenario, the network delay and overhead increase as these protocols use more routing metrics, which in turn comes with higher process complexities.