# DMRVR: Dynamic Milk-Run Vehicle Routing Solution Using Fog-Based Vehicular Ad Hoc Networks
## 2 Related Work
One restriction of this formulation was the assumption of a relatively significant number of supplier locations typical in product delivery cases but not typically encountered in OEM collecting milk-run systems. The only tardiness variable analyzed in the paper was related to all components' total delivery time at the OEM assembling line. Delays observed in the collecting process, at each supplier location, were indirectly considered as random variables. The same happened with delays in vehicle displacements over the routing network. As this solution has no vehicle communication technology, it only verifies if the vehicle is behind schedule when they arrive at the supplier. The vehicle can also not change the current route when it is stuck in a traffic jam, damaging the route performance. The evaluation did not use road traffic mobility simulators. A smart logistics vehicle management system in [20] collects information (vehicle condition, current location, speed, goods characteristics) from different sources, analyzes them, and makes decisions. This solution comprises three modules: (a) data collection module using sensors and RFID tags; (b) communication module responsible for sending data to the control center; (c) computation module that uses big data techniques to analyze data. For text data, 2 g technology is used, and, for audio and video streaming, 3 g and 4 g should be used. The authors only described the system and its features but did not implement the solution. Data transmission (2 g, 3 g, and 4 g) can generate additional costs for the vehicle owner. [PERSON] et al. [5] proposed a dynamic vehicle routing solution for milk-run operations with time windows considering traffic jams. The Michigan ITS Center supplied real traffic data from freeways and highways in the Detroit metropolitan area. The solution uses the Gaussian Mixture Model (GMM) and Markov Decision Process (MDP) to model the recurrent congestion based on historical ITS traffic data. The pickup routes are created based on travel time, avoiding usually congested streets and highways. The application has one distribution center and four suppliers' sites. The evaluation compared the dynamic solution to a static solution, where routes were created only considering the fastest travel time. Although Ref. [5] has close similarities with the present work, it does not consider the time spent by the vehicle when collecting cargo at the supplier's premises, considering only the vehicle travel times along the arcs of the route. However, in our work, we assume all the added times to form the total time up to delivering the components at the OEM, due to the diverse random nature of the variables and the specific objectives of this research. Additionally, this solution does not use any vehicular communication. The authors in [10] proposed a vehicle routing scheme to perform an OEM milk-run pickup service that considers supplier production line delays. The pickup vehicles have a predefined pickup route created by a Simulated Annealing (SA) algorithm. The solution performs the entire pickup operation within a time window determined by the OEM. The solution calculates delay probability at the supplier once the pickup vehicle arrives. The vehicle waits for a predefined time, and, after that, if the delay continues, it heads to the next supplier, and an auxiliary pickup vehicle is sent in its place. The delay is only verified while the vehicle is at the supplier, forcing it to stay there, at least for the predefined time. A route guidance application that uses data analysis is proposed by [44]. Real-time traffic data are acquired by RSUs and sent to a Traffic Command Center (TCC), which can calculate the optimal route for a vehicle. RSUs located on each road section measures the traffic flow by the received Cooperative Awareness Messages (CAMs) from the vehicles and send the flow information to the TCC using LTE. A car sends a request to the TCC to get the shortest route to its destination.