Ad hoc networks are gaining increasing popularity in recent years because of their ease of deployment. No wired base station or infrastructure is supported, and each host communicates one another via packet radios. In ad hoc networks, nodes are mobile which bring many challenges, such as network connectivity, topology change, link characteristic, and etc. In this research work, a novel model to analyze the link stability in mobile ad hoc networks is proposed. In the proposed analytical model, between each communicating pair, one node is considered to be stationary while the other moves relative to it. With this method, the mobility models defined in this dissertation can be approximated as a fluid flow model. Using the result of the fluid flow model, the analytical model for the link duration is obtained, which is used to obtain the link holding time and the link breaking probability of a communicating pair. The distribution of a routing path duration and the routing path breaking probability are also obtained by extending the models of the link duration and the link breaking probability. These results of link and routing path stabilities are serviced as ground knowledge to obtain the performance of medium access control (MAC) protocol considering node mobility. MAC protocols are a fundamental element that determines the efficiency in sharing the limited communication bandwidth of wireless channels. IEEE 802.11 distributed coordination function (DCF) MAC protocol is the most widely used MAC protocol in ad hoc networks due to its compatibility with the IEEE 802 protocol suite. Since the release of the IEEE 802.11 standard, many research efforts have been devoted to modeling the performance of this protocol. However, most of studies are confined to the stationary performance where the nodes are immobile. In this research work, we employ the link and routing path stability models to analyze the performance of the IEEE 802.11 DCF MAC protocol in dynamic environment. To the best of our knowledge, this is the first time to evaluate the performance of this protocol with mobility. Another contribution of this research work is to analyze the performance of the IEEE 802.11 DCF MAC protocol with capture effect. Currently, most analytical models assume that all received packets at the receiver have the same physical conditions (same power, same coding, etc), so when two or more nodes transmit their packets at the same time, the collision happens and all packets involved are destroyed, which may not be the case in reality due to capture effect. In this research work, we provide an analytical model to obtain the probability of capture effect. We use this probability of capture effect to analyze the throughput of the IEEE 802.11 DCF MAC protocol in ad hoc networks considering path loss, multipath fading, and shadowing. Wireless channel is time-varying and error prone. The packet transmission can be failed due to transmission errors. In this research work, a refined analytical model is presented to evaluate the performance of the IEEE 802.11 DCF MAC protocol with time-varying wireless channel. In the proposed model, the time-varying wireless channel is modeled by a finite-state Markov (FSM) chain. In each channel state, the operation of the IEEE 802.11 DCF MAC protocol is modeled by an embedded Markov chain. Using this model, the throughput of the DCF protocol can be theoretically calculated. The results show that the performance of the DCF protocol strongly depends on the network size, the incoming traffic loads, and the bit error rate (BER). When the incoming traffic load is light, the throughput increases when the network size grows. When the network works under heavy (saturated) condition, the throughput decreases when the network size grows. The throughput always degrades when increasing BER regardless the network size and the traffic load.