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Path duration is an important design parameter that determines the performance of a mobile ad hoc network (MANET). For example, it can be used to estimate the route expiry time parameter for routes in “on demand” routing protocols. This paper proposes an analytical model to estimate path duration in a MANET using the random way point mobility model as a reference. The salient feature of the proposed model is that it establishes a relationship between path duration and MANET design parameters including node density, transmission range, number of hops, and velocity of nodes. Although this relationship has been previously demonstrated through simulations, a detailed analytical model is not available in the literature to present. In particular, the relationship between path duration and node density has not been derived in previous models. The accuracy of the proposed model is validated by comparing the results obtained from the analytical model with the experimental results available in literature and with the results of simulations carried out in ns-2. [ABSTRACT FROM PUBLISHER]

Abstract: In this paper, we propose a protocol for dynamic reconfiguration of ad-hoc wireless networks with movable base stations in presence of obstacles. Hosts are assigned to base stations according to a probabilistic throughput function based on both the quality of the signal and the base station load. In order to optimize space coverage, base stations cluster hosts using a distributed clustering algorithm. Obstacles may interfere with transmission and obstruct base stations and hosts movement. To overcome this problem, we perform base stations repositioning making use of a motion planning algorithm on the visibility graph based on an extension of the bottleneck matching technique. We implemented the protocol on top of the NS2 simulator as an extension of the AODV. We tested it using both Random Way Point and Reference Point Group mobility models properly adapted to deal with obstacles. Experimental analysis shows that the protocol ensures the total space coverage together with a good throughput on the realistic model (Reference Point Group) outperforming both the standard AODV and DSR. [ABSTRACT FROM AUTHOR]

This letter presents an analytical framework of the cell stay time (CST) in wireless LAN environment. CST is an important parameter that can be used to estimate how long a mobile user will stay in a particular cell and how many cells he will probably visit during his call holding time. CST can be also used to make predictive advanced reservations. A probability density function (p.d.f.) of the CST is obtained and an analytical expression of its main parameters such as the average and standard deviation values is outlined as a function of the average mobile user speed and cell radius [ABSTRACT FROM PUBLISHER]