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In order to increase the penetration of electric vehicles, a network of fast charging stations that can provide drivers with a certain level of quality of service (QoS) is needed. However, given the strain that such a network can exert on the power grid, and the mobility of loads represented by electric vehicles, operating it efficiently is a challenging problem. In this paper, we examine a network of charging stations equipped with an energy storage device and propose a scheme that allocates power to them from the grid, as well as routes customers. We examine three scenarios, gradually increasing their complexity. In the first one, all stations have identical charging capabilities and energy storage devices, draw constant power from the grid and no routing decisions of customers are considered. It represents the current state of affairs and serves as a baseline for evaluating the performance of the proposed scheme. In the second scenario, power to the stations is allocated in an optimal manner from the grid and in addition a certain percentage of customers can be routed to nearby stations. In the final scenario, optimal allocation of both power from the grid and customers to stations is considered. The three scenarios are evaluated using real traffic traces corresponding to weekday rush hour from a large metropolitan area in the US. The results indicate that the proposed scheme offers substantial improvements of performance compared to the current mode of operation; namely, more customers can be served with the same amount of power, thus enabling the station operators to increase their profitability. Further, the scheme provides guarantees to customers in terms of the probability of being blocked by the closest charging station. Overall, the paper addresses key issues related to the efficient operation of a network of charging stations.Comment: Published in IEEE Journal on Selected Areas in Communications July 201

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The present paper deals with bandwidth allocation and congestion avoidance in a broadband satellite with on‐board switching, oriented towards guaranteeing the Quality of Service (QoS) associated with various traffic/service classes as defined by ATM forum. At the core of the bandwidth allocation a novel uplink (UL) access protocol is proposed, based on a Multi‐Frequency Time Division Multiple Access (MF‐TDMA) primary access scheme, in conjunction with a downlink (DL) access protocol based on a more traditional Time Division Multiplex (TDM) scheme. This UL access protocol is complemented by a rate‐based congestion control protocol (consistent with ATM Forum recommendations), which is an adaptation to GEO satellites environment of the Explicit Rate Indication for Congestion Avoidance (ERICA) algorithm developed for terrestrial networks. The performance of both UL access and congestion avoidance schemes has been evaluated through extensive simulations and the results compared with those obtained with other protocols or by analytical approximations. Copyright © 1999 John Wiley & Sons, Ltd.