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The focus of this paper is to analyze the throughput performance of TCP Thhoe and Reno on a differentiated services network with correlated wireless losses. An analytical model of TCP on a wireless link with differentiated services (DiffServ) based on the packet train model is developed. The network model is based on the state dependent arrival process. A major contribution of this paper is an analytical model combining the performance of TCP throughput and DiffServ leading to a model that represents an almost complete network scenario. It is shown that DiflServ in a wireless channel with correlated error losses is possible if the prob' ability of the channel changing from a good state to a bad state is less than a particular value. It is also shown that TCP Reno has a higher sensitivity to DiffServ than Tahoe. Our analytical model is validated through a number of simulations. [ABSTRACT FROM AUTHOR]

This paper provides mobility estimation and pree-diction for a variant of the GSM network that resembles an ad hoc wireless mobile network in which base stations and users are both mobile. We propose using a Robust Extended Kalman Filter (REKF) to derive an estimate of the mobile user's next mobile base station from the user's location, heading, and altitude, to improve connection reliability and bandwidth efficiency of the underlying system. Our analysis demonstrates that our algorithm can successfully track the mobile users with less system complexity, as it requires measurements from only one or two closest mobile base stations. Further, the technique is robust against system uncertainties caused by the inherent deterministic nature of the mobility model. Through simulation, we show the accuracy of our prediction algorithm and the simplicity of its implementation. [ABSTRACT FROM AUTHOR]

Several channel-allocation algorithms have been pro- posed in the literature for traditional cellular networks with static base stations (BS5), while not much attention has been given to channel-allocation problems for cellular networks where BSs are mobile. In cellular networks with mobile BSs (MBSs), the network topology is dynamic due to the mobility of the BSs. This makes the channel-allocation problem in such networks more challenging. Moreover, the MBSs may fail and degrade the performance of the cellular network. Therefore, it is desirable that the channel- allocation algorithm be fault tolerant. Thus, even in the presence of failure of the MBSs, the channel-allocation algorithm should work reasonably well. It is also desirable to design a channel-allocation approach that guarantees that the request from a mobile host (MH) is responded to in a timely manner. In this paper, a distributed dynamic channel-allocation algorithm that addresses these problems in cellular networks with MBSs is proposed. The proposed algorithm is fault tolerant and guarantees that the time to respond to an MH's request for supporting a call is upperbounded. The performance evaluation of the proposed algorithm shows that the proposed algorithm performs well, even in the presence of failure of the MBSs. [ABSTRACT FROM AUTHOR]