A Mobile Ad-hoc NETwork (MANET) is a collection of wireless mobile nodes forming a self-configuring network without using any existing infrastructure. MANETs catch the great attention of researchers because of its unique characteristics like independent of infrastructure, dynamic topology behavior, limited energy source, multihop routing, mobility of nodes etc. All these characteristics chase lots of challenges about security, reliability and performance issues. These are becoming very attractive and useful in many kinds of communication and networking applications. Understanding the factors that affect the path connection availability in multi-hop ad hoc networks can help to understand the path stability under various degrees of system dynamics. In addition, the connection availability of paths can be used as a global measure for the performance of ad hoc networks. There is very little analytical study that provides a closed form solution for analytical analysis of connection availability of paths in multihop ad hoc networks with Poison arrival time. Also, the hidden node problem is not yet addressed in the analytical study. This work proposes a closed form solution for this problem using a new stochastic reward net model. The influences of different factors, such as the number of nodes in the network, transmission range, tradeoff of power dissipation of individual nodes with network connectivity and battery life, network area size, data transmission rate, and routing protocol on the path connection availability are investigated. The system dynamics and various transitions are modeled using SRN modeling to derive analytical measurements of system reliability and availability. The proposed SRN model is simulated using PIPE (Platform Independent Petri Net Simulator). The system model and the model parameters are validated by extensive simulations using OMNeT ++.