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This article models the multihop data-routing in vehicular ad-hoc networks as multiple criteria decision making (MCDM) in four steps. First, the criteria that have impact on the performance of the network layer are captured and transformed into fuzzy sets. Second, the fuzzy sets are characterized by fuzzy membership functions (FMFs), which are interpolated (curve fitting) based on the data collected from massive experimental simulations. Third, the analytical hierarchy process (AHP) is exploited to identify the relationships among the criteria. Fourth, multiple fuzzy rules are determined and the Takagi–Sugeno–Kang (TSK) inference system is employed to infer and aggregate the final forwarding decision. Through integrating techniques of MCDM, FMF, AHP, and TSK, we design a distributed and opportunistic data routing protocol, namely, vehicular environment fuzzy router which targets vehicle-to-vehicle (V2V) communication and runs in two main processes—road segment selection (RSS) and relay vehicle selection (RVS). RSS is intended to select multiple successive junctions through which the packets should travel from the source to the destination, while RVS process is intended to select relay vehicles within the selected road segment. The experimental results show that our protocol performs and scales well with both network size and density, considering the combined problem of end-to-end packet delivery ratio and end-to-end latency.

Data dissemination toward static sinks causes the nearby nodes to deplete their energy quicker than the other nodes in the field (i.e., this is referred to as the hotspot problem). Accordingly, topology disruptions will occur and no data will be delivered to the sink. Mobile sinks are proposed to solve the hotspot problem in wireless sensor networks; they provide a load balancing and an energy consumption balancing for the whole network. However, sink mobility introduces new challenges (e.g., frequent location updates and packets delay). In this paper, we proposed a distributed sink-oriented dissemination protocol called Sink-oriented Tree based Data Dissemination (STDD). STDD constructs just one main dissemination tree for each mobile sink. When the access node is changed, the main tree will be updated and maintained to guarantee the shortest path to the mobile sinks. The updated and maintained tree is not a new tree; however, it is just a new version with only a few changes in a few levels of the main tree itself. Simulations show that STDD achieves a significant performance in terms of latency, network lifetime, delivery rate, and energy consumption compared with the state-of-the-art approaches.