The Experts below are selected from a list of 6111 Experts worldwide ranked by ideXlab platform
Chenn-jung Huang - One of the best experts on this subject based on the ideXlab platform.
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A Self-Adaptive Bandwidth Reservation Scheme for 4G Mobile WiMAX
2007 International Workshop on Cross Layer Design, 2007Co-Authors: Chenn-jung Huang, Chih-tai Guan, Dian-xiu Yang, Yi-ta Chuang, You-jia ChenAbstract:Many mechanisms based on Bandwidth Reservation have been proposed in the literature to decrease connection dropping probability for handoffs in cellular communications. The handoff events occur at a much higher rate in packet-switched 4G mobile WiMAX networks than in traditional cellular systems. In this paper, a self-adaptive Bandwidth Reservation schemes, which adopts a probabilistic mobility prediction model to estimate the Bandwidth required in neighboring cells, is proposed to reduce the forced termination probability of multimedia handoffs in 4G mobile WiMAX networks. Via cross-layer design, it exploits 4G mobile WiMAX advantages by using the Bandwidth Reservation. The simulation results show that the proposed scheme can achieve superior performance than the representative Bandwidth-reserving schemes in the literature when performance metrics are measured in terms of the forced termination probability for the handoffs, the call blocking probability for the new connections and Bandwidth utilization.
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Application of support vector machines to Bandwidth Reservation in sectored cellular communications
Engineering Applications of Artificial Intelligence, 2005Co-Authors: Chenn-jung HuangAbstract:Many mechanisms based on Bandwidth Reservation have been proposed in the literature to decrease connection dropping probability for handoffs in cellular communications. The handoff events occur at a much higher rate in sectored cellular networks than in traditional cellular systems. An efficient Bandwidth Reservation mechanism for the neighboring cells is therefore critical in the process of handoff during the connection of multimedia calls to avoid the unwillingly forced termination and waste of limited Bandwidth in the sectored cellular communications, particularly when the handoff traffic is heavy. In this paper, a self-adaptive Bandwidth Reservation scheme, which adopts support vector machines technique, is proposed to reduce the forced termination probability. Meanwhile, a channel-borrowing technique is used to decrease the new call-blocking probability of real-time traffic. The simulation results show that the proposed scheme can achieve superior performance than the representative Bandwidth-reserving schemes in sectored cellular networks in the literature when performance metrics are measured in terms of the forced termination probability and the new call- blocking probability.
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A self-adaptive Bandwidth Reservation scheme for sectored cellular communications
Information Sciences, 2004Co-Authors: Chenn-jung HuangAbstract:Many mechanisms based on Bandwidth Reservation have been proposed in the literature to decrease connection dropping probability for handoffs in cellular communications. The handoff events occur at a much higher rate in sectored cellular networks than in traditional cellular systems. An efficient Bandwidth Reservation mechanism for the neighboring cells is therefore critical in the process of handoff during the connection of multimedia calls to avoid the unwillingly forced termination and waste of limited Bandwidth in the sectored cellular communications, particularly when the handoff traffic is heavy. In this paper, a self-adaptive Bandwidth Reservation scheme, which employs a neural fuzzy Bandwidth-reserving estimator, is proposed to reduce the forced termination probability. Meanwhile, a channel borrowing technique is used to decrease the new call blocking probability of real-time traffic. The simulation results show that our scheme can achieve superior performance than traditional fixed Bandwidth-reserving scheme in sectored cellular networks when performance metrics are measured in terms of the forced termination probability and the new call blocking probability.
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Application of neuro-fuzzy technique to the Bandwidth Reservation for sectored cellular communications
The 2003 Congress on Evolutionary Computation 2003. CEC '03., 1Co-Authors: Chenn-jung Huang, Wei Kuang LaiAbstract:Many mechanisms based on Bandwidth Reservation have been proposed in the literature to decrease connection blocking probability and connection dropping probability in cellular communications. The handoff events occur at a much higher rate in sectored cellular networks than in traditional cellular systems. An efficient Bandwidth Reservation mechanism for the neighboring cells is therefore critical in the process of handoff during the connection of multimedia calls to avoid the unwillingly forced termination and waste of limited Bandwidth in the sectored cellular communications, particularly when the handoff traffic is heavy. A self-adaptive Bandwidth Reservation scheme which employs a neural fuzzy Bandwidth-reserving estimator, is proposed, and the simulation results show that our scheme can achieve superior performance than traditional fixed Bandwidth-reserving scheme in sectored cellular networks when performance metrics are measured in terms of the new call blocking probability and the forced termination probability.
Bernard Mans - One of the best experts on this subject based on the ideXlab platform.
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Bandwidth Reservation in multihop wireless networks complexity and mechanisms
International Conference on Distributed Computing Systems Workshops, 2004Co-Authors: Leonidas Georgiadis, Philippe Jacquet, Bernard MansAbstract:We show that link interferences in multihop wireless networks make the problem of selecting a path satisfying Bandwidth requirements an NP-complete problem, even under simplified rules for Bandwidth Reservation. This is in sharp contrast to path selection in wireline networks where efficient polynomial algorithms exist. We also describe a distributed mechanism for the problem of slot allocation according to Bandwidth Reservation in a wireless slotted environment.
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ICDCS Workshops - Bandwidth Reservation in multihop wireless networks: complexity and mechanisms
24th International Conference on Distributed Computing Systems Workshops 2004. Proceedings., 2004Co-Authors: Leonidas Georgiadis, Philippe Jacquet, Bernard MansAbstract:We show that link interferences in multihop wireless networks make the problem of selecting a path satisfying Bandwidth requirements an NP-complete problem, even under simplified rules for Bandwidth Reservation. This is in sharp contrast to path selection in wireline networks where efficient polynomial algorithms exist. We also describe a distributed mechanism for the problem of slot allocation according to Bandwidth Reservation in a wireless slotted environment.
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Bandwidth Reservation in Multihop Wireless Networks: Complexity, Heuristics and Mechanisms
2004Co-Authors: Géraud Allard, Leonidas Georgiadis, Philippe Jacquet, Bernard MansAbstract:We prove that link interferences in multihop wireless networks make the problem of selecting a path satisfying Bandwidth requirements an NP-complete problem, even under simplified rules for Bandwidth Reservation. This is in sharp contrast to path selection in wireline networks where efficient polynomial algorithms exist. We propose three heuristics to compute Quality of Service (QoS) routes in a multihop wireless networks considering interferences constraints. Our heuristics are based on Dijkstra’s shortest path algorithm in which we integrate the notion of node capacity in order to satisfy flow requirements. We show with several simulations that these heuristics allow computation of routes that save Bandwidth of nodes with low capacity and thus result in increased number of QoS-flows accepted by the network. Finally, we also describe a distributed mechanism for the problem of slot allocation according to Bandwidth Reservation in a wireless slotted environment.
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Bandwidth Reservation in Multihop Wireless Networks: Complexity and Mechanisms
2003Co-Authors: Leonidas Georgiadis, Philippe Jacquet, Bernard MansAbstract:We show that link interferences in wireless networks make multihop Bandwidth Reservation in such an environment an NP-complete problem. This is in sharp contrast to Bandwidth Reservation in wireline networks where efficient polynomial algorithms exist. We also consider the problem of slot allocation according to Bandwidth requirements in a wireless slotted environment. In the context of Mobile Ad Hoc Networks, we propose simple heuristics applicable to the OLSR routing protocol in order to find routes that satisfies requirements without impairing the performance of other connections.
Chita R Das - One of the best experts on this subject based on the ideXlab platform.
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A unified Bandwidth Reservation and admission control mechanism for QoS provisioning in cellular networks
Wireless Communications and Mobile Computing, 2004Co-Authors: Sunho Lim, Guohong Cao, Chita R DasAbstract:Summary We propose a unified framework consisting of a differential Bandwidth Reservation (DBR) algorithm and a Quality of Service (QoS)-aware admission control scheme to provide QoS guarantees to on-going connections in cellular networks. The differential Bandwidth Reservation policy uses a sector of cells in making the Bandwidth Reservation for accepting a new call. Based on the distance of the target cells in the sectors, two different Bandwidth Reservation policies are applied to optimize the connection dropping rate (CDR), while maintaining a competitive connection blocking rate (CBR). In addition, two possible mobile terminal (MT) movements are analyzed using the DBR mechanism. In the first case, no knowledge of an MT’s moving path is assumed to be known, while in the second case, prior knowledge of an user profile is used in Bandwidth Reservation, and it is called user profile-based DBR (UPDBR) algorithm. Using the DBR scheme, we propose an admission control algorithm that uses varying number of cells in a sector to meet admission decisions. Extensive simulation is performed to evaluate our methodology. Comparison of the proposed scheme with two prior schemes shows that our approach is not only capable of providing better QoS guarantees, but is also flexible in terms of using varying number of cells in satisfying the high-level QoS requirements. Copyright # 2004 John Wiley & Sons, Ltd.
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A unified Bandwidth Reservation and admission control mechanism for QoS provisioning in cellular networks: Research Articles
2004Co-Authors: Sunho Lim, Guohong Cao, Chita R DasAbstract:We propose a unified framework consisting of a differential Bandwidth Reservation (DBR) algorithm and a Quality of Service (QoS)-aware admission control scheme to provide QoS guarantees to on-going connections in cellular networks. The differential Bandwidth Reservation policy uses a sector of cells in making the Bandwidth Reservation for accepting a new call. Based on the distance of the target cells in the sectors, two different Bandwidth Reservation policies are applied to optimize the connection dropping rate (CDR), while maintaining a competitive connection blocking rate (CBR). In addition, two possible mobile terminal (MT) movements are analyzed using the DBR mechanism. In the first case, no knowledge of an MT's moving path is assumed to be known, while in the second case, prior knowledge of a user profile is used in Bandwidth Reservation, and it is called user profile-based DBR (UPDBR) algorithm. Using the DBR scheme, we propose an admission control algorithm that uses varying number of cells in a sector to meet admission decisions. Extensive simulation is performed to evaluate our methodology. Comparison of the proposed scheme with two prior schemes shows that our approach is not only capable of providing better QoS guarantees, but is also flexible in terms of using varying number of cells in satisfying the high-level QoS requirements. Copyright © 2004 John Wiley & Sons, Ltd.
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a differential Bandwidth Reservation policy for multimedia wireless networks
International Conference on Parallel Processing, 2001Co-Authors: Sunho Lim, Guohong Cao, Chita R DasAbstract:Provisioning of seamless communication for mobile terminal (MT) handoffs as well as guaranteeing a certain level of quality-of-service (QoS) to ongoing connections and new connections are critical issues in multimedia wireless networks. We present a differential Bandwidth Reservation(DBR) algorithm that can meet these requirements. For Bandwidth Reservation, the DBR scheme examines a sector of cells, which are located along the way to which the MT might move. The sector of cells are further divided into two regions depending on whether they have an immediate impact on the handoff or not. Two different Bandwidth Reservation policies are applied to cells in the two regions to optimize the connection dropping rate while maximizing the connection acceptance rate. Two possible MT movements are analyzed using the DBR mechanism. In the first case, no knowledge of the user's moving path is assumed to be available, while in the second case, prior knowledge of a user profile is used in Bandwidth Reservation, and is called the user profile-based DBR (UPDBR) algorithm. Simulation results indicate that the DBR algorithm is more adaptable to optimize the system performance in terms of call dropping rate compared to prior schemes. The UPDBR scheme can exploit the MT's moving path history for better Bandwidth utilization as well as reduction in the number of communication messages compared to the DBR scheme. The overall results show that the proposed schemes not only provide better performance, but also exploit the current state of the system in optimizing different performance parameters.
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ICPP Workshops - A differential Bandwidth Reservation policy for multimedia wireless networks
Proceedings International Conference on Parallel Processing Workshops, 1Co-Authors: Sunho Lim, Guohong Cao, Chita R DasAbstract:Provisioning of seamless communication for mobile terminal (MT) handoffs as well as guaranteeing a certain level of quality-of-service (QoS) to ongoing connections and new connections are critical issues in multimedia wireless networks. We present a differential Bandwidth Reservation(DBR) algorithm that can meet these requirements. For Bandwidth Reservation, the DBR scheme examines a sector of cells, which are located along the way to which the MT might move. The sector of cells are further divided into two regions depending on whether they have an immediate impact on the handoff or not. Two different Bandwidth Reservation policies are applied to cells in the two regions to optimize the connection dropping rate while maximizing the connection acceptance rate. Two possible MT movements are analyzed using the DBR mechanism. In the first case, no knowledge of the user's moving path is assumed to be available, while in the second case, prior knowledge of a user profile is used in Bandwidth Reservation, and is called the user profile-based DBR (UPDBR) algorithm. Simulation results indicate that the DBR algorithm is more adaptable to optimize the system performance in terms of call dropping rate compared to prior schemes. The UPDBR scheme can exploit the MT's moving path history for better Bandwidth utilization as well as reduction in the number of communication messages compared to the DBR scheme. The overall results show that the proposed schemes not only provide better performance, but also exploit the current state of the system in optimizing different performance parameters.
Hyong S. Kim - One of the best experts on this subject based on the ideXlab platform.
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a predictive Bandwidth Reservation scheme using mobile positioning and road topology information
IEEE ACM Transactions on Networking, 2006Co-Authors: Wee-seng Soh, Hyong S. KimAbstract:In cellular networks, an important practical issue is how to limit the handoff dropping probability efficiently. One possible approach is to perform dynamic Bandwidth Reservation based on mobility predictions. With the rapid advances in mobile positioning technology, and the widespread availability of digital road maps previously designed for navigational devices, we propose a predictive Bandwidth Reservation scheme built upon these timely opportunities. In contrast to the common practice of utilizing only incoming handoff predictions at each cell to compute the Reservations, our scheme is more efficient as it innovatively utilizes both incoming and outgoing handoff predictions; it can meet the same target handoff dropping probability by blocking fewer new calls. The individual base stations are responsible for the computations, which are shown to be simple enough to be performed in real-time. We evaluate the scheme via simulation, along with five other schemes for comparison. Simulation results show that those schemes that rely on positioning information are significantly more efficient than those that do not. Our scheme's additional use of the road topology information further improves upon this advantage, bringing the efficiency closer to the bound set by a benchmark scheme that assumes perfect knowledge about future handoffs.
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A Predictive Bandwidth Reservation Scheme Using
2006Co-Authors: Wee-seng Soh, Hyong S. KimAbstract:In cellular networks, an important practical issue is how to limit the handoff dropping probability efficiently. One possible approach is to perform dynamic Bandwidth Reservation based on mobility predictions. With the rapid advances in mobile positioning technology, and the widespread availability of dig- ital road maps previously designed for navigational devices, we propose a predictive Bandwidth Reservation scheme built upon these timely opportunities. In contrast to the common practice of utilizing only incoming handoff predictions at each cell to compute the Reservations, our scheme is more efficient as it innovatively utilizes both incoming and outgoing handoff predictions; it can meet the same target handoff dropping probability by blocking fewer new calls. The individual base stations are responsible for the computations, which are shown to be simple enough to be performed in real-time. We evaluate the scheme via simulation, along with five other schemes for comparison. Simulation results show that those schemes that rely on positioning information are significantly more efficient than those that do not. Our scheme's additional use of the road topology information further improves upon this advantage, bringing the efficiency closer to the bound set by a benchmark scheme that assumes perfect knowledge about future handoffs.
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dynamic Bandwidth Reservation in cellular networks using road topology based mobility predictions
International Conference on Computer Communications, 2004Co-Authors: Wee-seng Soh, Hyong S. KimAbstract:In cellular networks, an important call-level quality-of-service (QoS) issue is how to limit the probability of forced termination during handoffs. One solution is to predict the trajectory of mobile terminals so as to perform Bandwidth Reservation in advance. With the vision that future mobile devices are likely equipped with reasonably accurate positioning capability, we propose a novel mobility prediction technique that incorporates both mobile positioning information and road topology knowledge. We then develop an adaptive Bandwidth Reservation scheme that dynamically adjusts the Reservation at each base station according to both incoming and outgoing hand-off predictions generated using our mobility prediction technique. We evaluate the performance of the scheme via simulations, along with six other schemes for comparison purposes. Results agree with intuition that schemes which incorporate more knowledge are able to achieve better Reservation efficiency. Our scheme is shown to achieve the best efficiency among all realizable schemes simulated.
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Dynamic Bandwidth Reservation in hierarchical wireless ATM networks using GPS-based prediction
Gateway to 21st Century Communications Village. VTC 1999-Fall. IEEE VTS 50th Vehicular Technology Conference (Cat. No.99CH36324), 1999Co-Authors: Wee-seng Soh, Hyong S. KimAbstract:In this paper, we propose a distributed admission control scheme based on dynamic Bandwidth Reservation, with the aid of GPS to trade the position of the mobile terminal (MT) and predict its trajectory. We consider both wireless and wired links as potential bottlenecks and perform Reservation in both types of links. By predicting a MT's target handoff cell and its remaining time to handoff, Bandwidth Reservation can be performed dynamically and efficiently. We perform simulations using an arbitrary hierarchical wireless ATM network with 256 cells, and show that the proposed scheme is able to prioritize handoff requests with moderate tradeoff of the blocking probability for new calls. We also show that the proposed scheme does not affect the amount of Bandwidth utilization significantly, and the amount of prediction errors is approximately 1% of the total number of handoffs.
Marcin Stasiak - One of the best experts on this subject based on the ideXlab platform.
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asymmetric convolution algorithm for blocking probability calculation in full availability group with Bandwidth Reservation
Communication Systems and Networks, 2008Co-Authors: Mariusz Glabowski, Adam Kaliszan, Marcin StasiakAbstract:The paper proposes a new approximate calculation method of occupancy distribution and blocking probability in the full-availability group (FAG) with multi-rate traffic streams and Bandwidth Reservation. The algorithm involves calculation of system state probabilities by a convolution operation. In the paper, an effective method of calculating state probabilities in a Reservation space of the system is derived. The analytical results of blocking probabilities in the FAG with Bandwidth Reservation, obtained on the basis of the proposed analytical method, are compared with the data obtained on the basis of other known analytical methods and with the simulation results. The accuracy of the proposed method is evaluated for different multi-rate Bernoulli (Erlang), Poisson (Engset), Pascal traffic streams. The method proposed is characterised by lower complexity than the convolution algorithm for the FAG with Bandwidth Reservation devised earlier.
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Evaluation of traffic characteristics of UMTS with Bandwidth Reservation and handoff mechanism
2007 IEEE International Conference on Telecommunications and Malaysia International Conference on Communications, 2007Co-Authors: Mariusz Glabowski, Maciej Sobieraj, Marcin StasiakAbstract:The paper proposes an analytical method of blocking probability calculation in UMTS networks with Bandwidth Reservation and connection handover mechanism. The papers proposes also Reservation algorithms for a group of cells, exploiting the effects of connection handoff between cells. The proposed analytical model is based on the generalized model of a limited-availability group. The results of analytical calculations of blocking probability in a group of UMTS cells with Bandwidth Reservation are compared with simulation data.
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Blocking probability calculation in UMTS networks with Bandwidth Reservation, handoff mechanism and finite source population
2007 International Symposium on Communications and Information Technologies, 2007Co-Authors: Mariusz Glabowski, Maciej Sobieraj, Marcin StasiakAbstract:The paper proposes a new analytical approach to blocking probability calculation in wireless mobile networks with Bandwidth Reservation and connection handoff mechanisms, carrying a mixture of different traffic streams. This mixture can be composed of an arbitrary number of traffic classes, generated by a finite as well as an infinite population of traffic sources. The appropriate Bandwidth Reservation algorithm for a group of cells, exploiting the effects of connection handoff between cells, is also proposed. The results of analytical calculations of blocking probability in a group of UMTS cells with Bandwidth Reservation are compared with simulation data.
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Asymmetric Convolution Algorithm for Full-Availability Group with Bandwidth Reservation
2006 Asia-Pacific Conference on Communications, 2006Co-Authors: Mariusz Glabowski, Adam Kaliszan, Marcin StasiakAbstract:In the paper a new asymmetric convolution algorithm for the calculation of the occupancy distribution and the blocking probability in the full-availability group (FAG) with Bandwidth Reservation and multirate traffic streams is proposed. In the paper, an effective method of calculating state probabilities in a Reservation space of the system is derived. The analytical results of the blocking probabilities in the FAG with Bandwidth Reservation obtained on the basis of the proposed method, are compared with the simulation results. This comparison has proved a high accuracy of the proposed algorithm. The proposed asymmetric convolution algorithm can be applied for systems with Bandwidth Reservation and with arbitrary multirate traffic streams.
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AICT/ICIW - Blocking Probability Calculation in a FAG with Bandwidth Reservation
Advanced Int'l Conference on Telecommunications and Int'l Conference on Internet and Web Applications and Services (AICT-ICIW'06), 2006Co-Authors: M. Gabowski, Adam Kaliszan, Marcin StasiakAbstract:This paper presents a new method for blocking probability calculation in the full-availability group (FAG) with multi-rate traffic streams and Bandwidth Reservation. The proposed method is based on Iversen convolution algorithm worked out for systems without Bandwidth Reservation. The algorithm consists in calculation of system state probabilities by the convolution operation. In the paper special attention is paid to the method of calculating state probabilities in a Reservation space of the system. Analytical results of the blocking probabilities in the FAG with Bandwidth Reservation, obtained on the basis of the proposed method, are compared with simulation results.
