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Mobile Network (mobile + network)
Selected AbstractsPerformance analysis of a cellular mobile network with retrials and guard channels using waiting and first passage time measuresEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 4 2009A. Economou Most studies of modern cellular mobile networks concern performance measures directly computable from the stationary state probabilities such as the blocking probability and the mean traffic rates of the various kinds of calls. In this paper, we consider a cellular mobile system with retrials and guard channels for the handover calls, but we concentrate on performance measures related to the waiting and first passage times of the system. More concretely, we first build a Markovian model representing a station of the network and then we study the waiting time of a customer, the idle times of the guard channels and the time between successive lost calls. These measures shed light on the behaviour of the system and quantify the quality of service from both points of view of the customer and the administrator. Several numerical results illustrate the effect of the system parameters in its performance. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prioritisation of data partitioned MPEG,4 video over mobile networks,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 3 2001Stewart T. Worrall Despite much research in the field of mobile multimedia, delivery of real,time,interactive video over noisy wireless channels remains a challenging problem. Two of the major issues in providing true end,to,end mobile multimedia capability are interoperability between platforms and networks and the poor performance of video compression algorithms in error,prone environments. This paper presents a method for prioritising data partitioned MPEG,4 video in a way suitable for transmission over a mobile network. The effectiveness of the technique is demonstrated by examining the performance when transmitted using the Real,Time Transport protocol over GPRS (General Packet Radio Service) data channels under varying channel conditions. [source] Distribution learning for radio network planning tool simulationINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 12 2008Z. Nouir Abstract We propose a novel method that combines the simulation results of a model-based prediction tool with the knowledge contained in measurement data. This mixture of the a priori information and the posteriori knowledge aims at enhancing the prediction results by increasing their precision and quality. A multilayer perceptron (MLP) is trained to learn the mapping between the distributions of the measurement data and the simulation data. To make the complexity of the MLP tractable, we propose the utilization of independent component analysis (ICA). The ICA transformation makes the variables at the input of the MLP statistically independent so that it can perform its learning and generalization on individual one-dimensional distributions. Other contributions consist of the application of the k -means clustering algorithm on the incoming data and the use of the training data world model to enhance the generalization capability of the MLP. The world model consists of the aggregation of all the available data in the learning space. The proposed method is applied to a third generation mobile network to enhance the predictions of uplink and downlink base station loads. After a training performed on a given network configuration, mechanical antenna tilts are modified and we show that the results obtained by the supervised predictions are much closer to measurements than simulation results for cases that have not been encountered before. Copyright © 2008 John Wiley & Sons, Ltd. [source] Synchronization among neighbouring RNCs in a TD-CDMA mobile networkINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 5 2007Yin-Fu Huang Abstract In the paper, we use zone concepts, and also consider multiple-bunch in a TD-CDMA mobile network. In the multiple-bunch environment, we need a synchronization mechanism to avoid inter-RNC interferences. Here, we use an Informed-of message to transmit local resource allocation results to other neighbouring RNCs through a high-speed network. Thus, inter-RNC interferences can be avoided and the global resource allocation can be made with the message passing. Within the resource allocation algorithm, we also find maximal compatible cliques to achieve the best resource utilization, using the graph algorithm finding maximal cliques in graph theory. Through the simulation, we found that the SRU classification using Conservative strategy matching the SRU allocation using Aggressive strategy has the best performance among all combinations. Copyright © 2006 John Wiley & Sons, Ltd. [source] Distribution-based anomaly detection in 3G mobile networks: from theory to practiceINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 5 2010Alessandro D'Alconzo The design of anomaly detection (AD) methods for network traffic has been intensively investigated by the research community in recent years. However, less attention has been devoted to the issues which eventually arise when deploying such tools in a real operational context. We designed a statistical based change detection algorithm for identifying deviations in distribution time series. The proposed method has been applied to the analysis of a large dataset from an operational 3G mobile network, in the perspective of the adoption of such a tool in production. Our algorithm is designed to cope with the marked non-stationarity and daily/weekly seasonality that characterize the traffic mix in a large public network. Several practical issues emerged during the study, including the need to handle incompleteness of the collected data, the difficulty in drilling down the cause of certain alarms, and the need for human assistance in resetting the algorithm after a persistent change in network configuration (e.g. a capacity upgrade). We report on our practical experience, highlighting the key lessons learned and the hands-on experience gained from such an analysis. Finally, we propose a novel methodology based on semi-synthetic traces for tuning and performance assessment of the proposed AD algorithm. Copyright © 2010 John Wiley & Sons, Ltd. [source] Teletraffic capacity of CDMA cellular mobile networks and adaptive antennasINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 4 2002Abdulaziz S. Al-Ruwais The teletraffic capacity of a CDMA mobile network with adaptive antennas at the receiver base station is considered and a simplified expression for the system outage probability associated with the teletraffic capacity is obtained. Analytical as well as numerical results show that the outage probability, and consequently the teletraffic capacity of the system, is improved using adaptive antennas at the receiver base station. Copyright © 2002 John Wiley & Sons, Ltd. [source] IMS network signaling peering: Challenges and proposalBELL LABS TECHNICAL JOURNAL, Issue 4 2008Jean-Philippe Joseph IP Multimedia Subsystem (IMS) network peering is a key enabler that will help accelerate deployment of next-generation IMS-based networks. Today's early deployments of dispersed IMS networks require public switched telephone network (PSTN)/public land mobile network (PLMN) bridges for network interconnection between IMS islands. The PSTN/PLMN bridging arrangement is inefficient, however, in that it results in unnecessary settlements for the carriers. It further impedes the implementation of rich multimedia and Voice over IP (VoIP)-related services that require end-to-end Internet Protocol (IP) connectivity. Last, it perpetuates the reliance on the existing PSTN/PLMN network for voice calls among subscribers served by different IMS-based carriers. This paper analyzes in detail the IMS peering challenges from the perspective of Session Initiation Protocol (SIP) signaling peering. It discusses issues related to the routing of SIP messages, and addressing, address resolution, and discovery of peering points for IMS signaling peering. It further establishes that a new routing algorithm is needed that will allow signaling peering points to dynamically discover the "best" transit network among others for reaching a destination. In closing, it presents a high-level IMS signaling routing process that includes, among other benefits, support for number portability as a key function for inter-carrier IMS peering. © 2008 Alcatel-Lucent. [source] Access network discovery and selection in the evolved 3GPP multi-access system architectureEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 6 2010Joachim Sachs The system architecture evolution (SAE) of mobile networks specified in 3GPP release 8 comprises an evolved packet core (EPC) network to which different types of access networks can be connected. Inter-system mobility management enables users to change the access network while maintaining ongoing data sessions. One important functionality in a 3GPP system is how a mobile terminal discovers and selects available access networks. In this paper we describe the access network discovery and selection functionality used in 3GPP release 8; we explain the differences of the methods applied for 3GPP access networks (GERAN, UTRAN, E-UTRAN), for fixed or wireless non-3GPP access networks (e.g. WLAN, WiMAX), as well as the optimisation used for CDMA2000 access networks. Copyright © 2010 John Wiley & Sons, Ltd. [source] Performance analysis of a cellular mobile network with retrials and guard channels using waiting and first passage time measuresEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 4 2009A. Economou Most studies of modern cellular mobile networks concern performance measures directly computable from the stationary state probabilities such as the blocking probability and the mean traffic rates of the various kinds of calls. In this paper, we consider a cellular mobile system with retrials and guard channels for the handover calls, but we concentrate on performance measures related to the waiting and first passage times of the system. More concretely, we first build a Markovian model representing a station of the network and then we study the waiting time of a customer, the idle times of the guard channels and the time between successive lost calls. These measures shed light on the behaviour of the system and quantify the quality of service from both points of view of the customer and the administrator. Several numerical results illustrate the effect of the system parameters in its performance. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prioritisation of data partitioned MPEG,4 video over mobile networks,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 3 2001Stewart T. Worrall Despite much research in the field of mobile multimedia, delivery of real,time,interactive video over noisy wireless channels remains a challenging problem. Two of the major issues in providing true end,to,end mobile multimedia capability are interoperability between platforms and networks and the poor performance of video compression algorithms in error,prone environments. This paper presents a method for prioritising data partitioned MPEG,4 video in a way suitable for transmission over a mobile network. The effectiveness of the technique is demonstrated by examining the performance when transmitted using the Real,Time Transport protocol over GPRS (General Packet Radio Service) data channels under varying channel conditions. [source] Distribution-based anomaly detection in 3G mobile networks: from theory to practiceINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 5 2010Alessandro D'Alconzo The design of anomaly detection (AD) methods for network traffic has been intensively investigated by the research community in recent years. However, less attention has been devoted to the issues which eventually arise when deploying such tools in a real operational context. We designed a statistical based change detection algorithm for identifying deviations in distribution time series. The proposed method has been applied to the analysis of a large dataset from an operational 3G mobile network, in the perspective of the adoption of such a tool in production. Our algorithm is designed to cope with the marked non-stationarity and daily/weekly seasonality that characterize the traffic mix in a large public network. Several practical issues emerged during the study, including the need to handle incompleteness of the collected data, the difficulty in drilling down the cause of certain alarms, and the need for human assistance in resetting the algorithm after a persistent change in network configuration (e.g. a capacity upgrade). We report on our practical experience, highlighting the key lessons learned and the hands-on experience gained from such an analysis. Finally, we propose a novel methodology based on semi-synthetic traces for tuning and performance assessment of the proposed AD algorithm. Copyright © 2010 John Wiley & Sons, Ltd. [source] An adaptive resource reservation for vehicular mobile networksINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 5 2009I. Ben Hamida This paper presents the time-based bandwidth reservation (TBR) algorithm, suitable for handoff management in cellular systems. TBR is based on real-time measurements of mobile stations (position, velocity and acceleration). The scheme consists in sending reservation requests to the neighboring cells based on an extrapolation of the user's motion. The originality of our approach lies in dynamically adjusting the amount of time for which bandwidth has to be allocated and reserved in a cell. In addition, we propose an optimal channel requests arrangement (CRA) algorithm in order to improve the performance of TBR in terms of resource utilization. Finally, we propose VTBR, an adapted and extended version of TBR for better support of vehicular network specificities where service degradation or forced call termination may occur owing to frequent handoffs. Detailed simulation results for TBR and VTBR schemes and a comparison with the guard channel scheme are presented. The results show that TBR and VTBR can efficiently improve the flow dropping probability. Copyright © 2008 John Wiley & Sons, Ltd. [source] Teletraffic capacity of CDMA cellular mobile networks and adaptive antennasINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 4 2002Abdulaziz S. Al-Ruwais The teletraffic capacity of a CDMA mobile network with adaptive antennas at the receiver base station is considered and a simplified expression for the system outage probability associated with the teletraffic capacity is obtained. Analytical as well as numerical results show that the outage probability, and consequently the teletraffic capacity of the system, is improved using adaptive antennas at the receiver base station. Copyright © 2002 John Wiley & Sons, Ltd. [source] Efficient packet scheduling for heterogeneous multimedia provisioning over broadband satellite networks: An adaptive multidimensional QoS-based designINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 1 2009Hongfei Du Abstract With their inherent broadcast capabilities and reliable extensive geographical coverage, the broadband satellite networks are emerging as a promising approach for the delivery of multimedia services in 3G and beyond systems. Given the limited capacity of the satellite component, to meet the diverse quality of service (QoS) demands of multimedia applications, it is highly desired that the available resources can be adaptively utilized in an optimized way. In this paper, we draw our attention on the development and evaluation of an efficient packet scheduling scheme in a representative broadband satellite system, namely satellite digital multimedia broadcasting (SDMB), which is positioned as one of the most attractive solutions in the convergence of a closer integration with the terrestrial mobile networks for a cost-effective delivery of point-to-multipoint services. By taking into account essential aspects of a successful QoS provisioning while preserving the system power/resource constraints, the proposed adaptive multidimensional QoS-based (AMQ) packet scheduling scheme in this paper aims to effectively satisfy diverse QoS requirements and adaptively optimize the resource utilization for the satellite multimedia broadcasting. The proposed scheme is formulated via an adaptive service prioritization algorithm and an adaptive resource allocation algorithm. By taking into account essential performance criteria, the former is capable of prioritizing contending flows based on the QoS preferences and performance dynamics, while the latter allocates the resources, in an adaptive manner, according to the current QoS satisfaction degree of each session. Simulation results show that the AMQ scheme achieves significantly better performance than those of existing schemes on multiple performance metrics, e.g. delay, throughput, channel utilization and fairness. Copyright © 2008 John Wiley & Sons, Ltd. [source] Auctions Versus Beauty Contests: The Allocation of UMTS Licences in EuropeANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 1 2003L. Cartelier The deployment of the so-called UMTS 3rd generation mobile networks is a step of vital importance for the promotion of competition in the telecommunications sector. The provision of high-traffic services presupposes that operators have access to the hertzian spectrum. The hertzian spectrum is a natural resource whose scarcity derives from the fact that only part of it is usable, for both technical and economic reasons. While the resource was sufficient to meet users' needs, the hertzian spectrum was allocated for little or no charge, on the principle of ,first come, first served'. However, with the explosion of technical progress in transmission technologies, new applications and new forms of use appeared, leading to a drastic increase in potential demand. It is in this context that the idea of charging for use of the spectrum arose, so as to discourage uneconomical use of the resource (e.g. stockpiling, wastage), to ensure a fair allocation between competing users and to forestall congestion. The purpose of this paper is first to examine the procedures for the allocation of hertzian spectrum operating licences, from the points of view of efficiency, transparency and sharing of the surplus. We shall then compare the results from the two approaches that were actually used in Europe: the open ascending auction and the beauty contest, before turning our attention to new forms of public action that result from the process of liberalization. [source] | |||||||||||||