A Mobile Ad hoc Network (MANET) is a collection of mobile nodes that operate without any backbone infrastructure support. Implementation of MANETS is very useful in certain military applications and during emergency situations such as earth quakes and re accidents. In MANETS, routing decisions are governed by the operating routing protocol. Mobility is one of the most important factors to be considered in developing such routing protocols. The e ect of mobility on a network is quanti ed in terms of link and route duration times. Therefore, understanding mobility and its e ect on path duration will de nitely help in coming up with a better routing algorithm. In this thesis, we discuss the importance of mobility and its impact on a network. Also, we tried to come up with an enhanced version of the mathematical model for the path duration estimate from an existing model. One application of the path duration estimate is to select a route with maximum expiry time unlike most of the routing algorithms which choose a path based on shortest path. First, we estimate route expiry time with a single relay node between the source and the destination. With this simple scenario, we analyze how long it takes for a relay node to come out of the transmission range of the source node. Then, we generalize the analysis for h number of hops used to reach destination. Also, the e ect on path duration due to parameters such as transmission range, node mobility, relative velocity, and number of hops in the route is studied. Simulations are performed in MATLAB and the signi cance of the proposed model is discussed with an analysis of the results obtained.