Abstract Mobility management, which includes location management and handoff management, is essential in cellular wireless networks to provide service to mobile users. Location management enables call delivery to mobile users, while handoff management maintains the connectivity of ongoing calls while users move between cells. In next generation networks, mobile users will avail themselves with terminals capable of accessing wireless networks employing multiple technologies, thus making the task of mobility management more challenging. This paper reviews recent developments in location management, and surveys methods for handoff management between heterogeneous systems. Methods for inter‐system handoffs in packet‐switched inter‐networks are discussed according to the protocol layer in which the handoffs take place, i.e., network layer, transport layer, and application layer. Open problems for mobility management in future wireless networks are also presented. Copyright © 2010 John Wiley & Sons, Ltd.

Advances in mobile networks and positioning technologies have made location information a valuable asset in vehicular ad-hoc networks (VANETs). However, the availability of such information must be weighted against the potential for abuse. In this paper, we investigate the problem of alleviating unauthorized tracking of target vehicles by adversaries in VANETs. We propose a vehicle density-based location privacy (DLP) scheme which can provide location privacy by utilizing the neighboring vehicle density as a threshold to change the pseudonyms. We derive the delay distribution and the average total delay of a vehicle within a density zone. Given the delay information, an adversary may still be available to track the target vehicle by a selection rule. We investigate the effectiveness of DLP based on extensive simulation study. Simulation results show that the probability of successful location tracking of a target vehicle by an adversary is inversely proportional to both the traffic arrival rate and the variance of vehicles' speed. Our proposed DLP scheme also has a better performance than both Mix-Zone scheme and AMOEBA with random silent period.

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Wireless ad-hoc networks can experience significant performance degradation under fading channels. Diversity through space has been shown to be an effective way of combating wireless fading with the multiple-input-multiple-output (MIMO) technique by transmitting correlated information through multip

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