A mobile ad-hoc network (MANET) is basically called as a network without any central administration or fixed infrastructure. It consists of a number of mobile nodes that use to send data packets through a wireless medium. There is always a need of a good routing protocol in order to establish the connection between mobile nodes since they possess the property of dynamic changing topology. Further, in all the existing routing protocols, mobility of a node has always been one of the important characteristics in determining the overall performance of the ad hoc network. Thus, it is essential to know about various mobility models and their effect on the routing protocols. In this paper, we have made an attempt to compare different mobility models and provide an overview of their current research status. The main focus is on Random Mobility Models and Group Mobility Models. Firstly, we present a survey of the characteristics, drawbacks and research challenges of mobility modeling. At the last we present simulation results that illustrate the importance of choosing a mobility model in the simulation of an ad hoc network protocol. Also, we illustrate how the performance results of an ad hoc network protocol drastically change as a result of changing the mobility model simulated.

In this paper, we discuss the basic routing technique of ants and study the change in pheromone values at each node. Also the optimal paths can then be computed based on the shortest cumulative pheromone count between source and destination nodes. AntNet is a distributed multi-agent system inspired by the stigmergy model of communication observed in ant colonies. The ants or control packets collect information about the network conditions and are used to update and maintain the routing tables. Ants based routing is gaining more popularity because of its adaptive and dynamic nature. A number of Swarm Intelligence based, more specially Ant Colony Optimization (ACO) based routing algorithms are proposed by researchers. A version of ant routing protocol called AntNet has been implemented to work within the network simulator ns-2. Routing tables and Pheromone tables have been computed for each node in the network. On the basis of these tables we have tried to compute the shortest and most optimal path between source node and destination node.