Vehicular ad hoc networks (VANETs) are a type of ad hoc networks where the node movements are high and there will be instant communication between the vehicles (nodes). In this chapter, the authors propose a real-time simulation of vehicular ad hoc networks using simulation of urban mobility (SUMO) in two cases: 1) user-defined road structure and 2) roads designed through open street maps. In both these cases, cars, buses, trucks, pedestrians, and bicycles will be running in the roads. Most of the vehicles will be following the Euro emission norms. Later these cars will be modelled as nodes in a network and analyse the various network performance metrics like throughput and packet delivery ratio were computed.

There is great demand for VANETs in recent times. VANETs enable vehicular communication with the advent of latest trends in communication like 5G technology, software-defined networks, and fog and edge computing. Novel applications are evolving in recent times on VANETs with the proliferation of internet of things. Real test bed implementation is not always feasible with various limitations like expenditure and manpower and requires more time to experiment with the new facets of VANETs. Hence, the researchers should be aware of the variety of simulation tools that are capable of running VANET simulations. Simulation is a powerful tool in developing any critical/complex system that constitutes minimum cost and effort. The simulation tools of VANETs should support multiple mobility models, real-world communication protocols, and traffic modeling scenarios. This chapter gives a clear view on available tools and their characteristics on VANETs for research purposes.

Keywords: Wireless networks, Sensors, Power estimation, Wireless sensor networks. INTRODUCTIONBoth the commercial users and the research fields have shown an increased interest in the wireless sensor network (WSN) technology recently. WSN is a structured or unstructured arrangement of nodes (i.e., sensors motes or transducers) deployed in a geographical area for continuous monitoring and recording the activities of that area. It records whether any additions, eliminations, or variations are introduced in the area being monitored.The area may be bounded or unbounded and the nodes can be mobile or immobile depending upon the application. Typically, a sensor mote is small device which has a sensing subsystem for data acquisition, processing subsystem for local data processing, and wireless data communication system [6].WSNs are being deployed in a huge range of applications from health, space, and military to commercial and environmental observations and data analysis. However, due to its wireless nature, several constraints are imposed on the operation of the network. The nodes in the WSNs are self-powered, i.e., they work on batteries, which make it limited resource. The power is used in every other task such as computation, transmission continuous monitoring, and making power management a critical issue to be addressed in WSNs. There are performance factors that directly depend on power availability in the nodes. The node ability to transmit over long ranges, transmit for a longer time, and transmit with required signal strength to avoid noise interference depends on the power available in the battery of the node.The network link lifetime is the time till the last node drains out of all of its energy and is expected to extend till the required application request is fulfilled. Along with these, the link quality, channel bandwidth, throughput, average end-to-end time delay, and average residual energy are some other factors that have to be optimized as per the demands of the applications. The designing of routing protocols thus takes care of all or few of the network optimization parameters. The routing in turn depends on the application requirements, whether it is over a bounded or unbounded area, whether it is time critical or data critical, etc. The routing algorithm should be given the decision-making power on that level where it decides to use which particular technique is to be used for building a route depending on the existing configuration and network conditions at that moment.