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Connection Admission Control for a WDM Optical Network Based on Traffic Monitoring and Bandwidth Release

ALMEIDA, Helvecio M.; QUEIROZ, Eduardo M. G. de; CESAR, Amilcar C.
Fonte: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC Publicador: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Tipo: Artigo de Revista Científica
Português
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We proposed a connection admission control (CAC) to monitor the traffic in a multi-rate WDM optical network. The CAC searches for the shortest path connecting source and destination nodes, assigns wavelengths with enough bandwidth to serve the requests, supervises the traffic in the most required nodes, and if needed activates a reserved wavelength to release bandwidth according to traffic demand. We used a scale-free network topology, which includes highly connected nodes ( hubs), to enhance the monitoring procedure. Numerical results obtained from computational simulations show improved network performance evaluated in terms of blocking probability.; Brazilian agency CNPq; Brazilian agency CAPES

Estudo de algoritmos de controle de admissão em servidores Web distribuídos com QoS; Study of admission control algorithms on QoS distibuted web server

Eustaquio, Paulo Sérgio Franco
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/06/2011 Português
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Esta dissertação de mestrado apresenta a prototipação de uma arquitetura denominada ServidorWeb com Diferenciação de Serviços (SWDS). O trabalho também apresenta a proposta, implementação e a avaliação de desempenho de dois algoritmos de controle de admissão denominados Algoritmo de Negociação e Algoritmo de Reserva de Conexões. O objetivo principal deste trabalho é a avaliação de desempenho dos algoritmos de controle de admissão no protótipo do SWDS. Como resultados, verificou-se que a Classe de maior prioridade consegue atender mais requisições que a Classe de menor prioridade em todos as configurações de carga. Também pode-se observar que o algoritmo de reserva de conexões consegue se adaptar a todas as variações de cargas; This masters dissertation presents the prototype of an architecture named SWDS. This work presents the proposal, implementation and performance evaluation of two admission control algorithms named negotiation algorithm and connection reserve algorithm. The aim of this work is to evaluate the performance of the control admission algorithms in the SWDS prototype. As a result, it could be seen the high priority Class met a higher number of requests than the low priority Class. Also it could be seen the connection reserve algorithm can adapt to all workloads variation

B-ISDN connection admission control and routing strategy with traffic prediction by neural networks

Neves, Joaquim E.; Almeida, Luís B.; Leitão, Mário J.
Fonte: IEEE Press Publicador: IEEE Press
Tipo: Conferência ou Objeto de Conferência
Publicado em /05/1994 Português
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The resource allocation in the Broadband Integrated Services Digital Network (B-ISDN) can be based in an overall network performance function described in this paper and named quality of operation. The quality of operation function is determined itself by bandwidth and quality of service functions. The traffic patterns of the quality of service for each call are predicted by neural networks. The applicability of the quality of operation function to connection admission control and call routing is proposed and supported by simulation results.

Distributed admission control for QoS and SLS management

Lima, Solange; Carvalho, Paulo; Freitas, Vasco
Fonte: Kluwer Publicador: Kluwer
Tipo: Artigo de Revista Científica
Publicado em /09/2004 Português
Relevância na Pesquisa
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This article proposes a distributed admission control (AC) model based on on-line monitoring to manage the quality of Internet services and Service Level Specifications (SLSs) in class-based networks. The AC strategy covers intra- and interdomain operation, without adding significant complexity to the network control plane and involving only edge nodes. While ingress nodes perform implicit or explicit AC resorting to service-oriented rules for SLS and QoS parameters control, egress nodes collect service metrics providing them as inputs for AC. The end-to-end operation is viewed as a cumulative and repetitive process of AC and available service computation.We discuss crucial key points of the model implementation and evaluate its two main components: themonitoring process and the AC criteria. The results show that, using proper AC rules and safety margins, service commitments can be efficiently satisfied, and the simplicity and flexibility of the model can be explored to manage successfully QoS requirements of multiple Internet services.

Managing services quality through admission control and active monitoring

Lima, Solange; Carvalho, Paulo; Santos, Alexandre; Freitas, Vasco
Fonte: Springer Publicador: Springer
Tipo: Conferência ou Objeto de Conferência
Publicado em /09/2003 Português
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We propose a lightweight traffic admission control scheme based on on-line monitoring which ensures multimedia services quality both intra-domain and end-to-end. The AC strategy is distributed, service-oriented and allows to control QoS and SLS without adding complexity to the network core. For each service class, AC decisions are driven by rate-based SLS control rules and QoS parameters control rules, defined and parameterized according to each service characteristics. These rules are essentially based on systematic on-line measurements of relevant QoS and performance parameters. Thus, from a practical perspective, we discuss and evaluate methodologies and mechanisms for parameter estimation. The AC criteria is evaluated as regards its ability to ensure service commitments while achieving high network utilization. The results show that the proposed model provides a good compromise between simplicity, service level guarantee and network usage, even for services with strict QoS requirements.

A distributed admission control model for CoS networks using QoS and SLS monitoring

Lima, Solange; Carvalho, Paulo; Santos, Alexandre; Freitas, Vasco
Fonte: IEEE Communication Society Press Publicador: IEEE Communication Society Press
Tipo: Conferência ou Objeto de Conferência
Publicado em /05/2003 Português
Relevância na Pesquisa
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Achieving an admission control strategy for CoS networks covering both intra-domain and end-to-end operation is still an open issue. This paper discusses how AC can be carried out without adding significant complexity to the network control plane and proposes a distributed service-oriented AC model for these networks. The model only involves the network edge nodes leaving the network core unchanged. Ingress nodes perform implicit or explicit service-dependent AC based on both QoS and SLSs utilization metrics, obtained through on-line edge-to-edge monitoring performed at egress nodes. From an end-to-end perspective, the flow request is used both for AC and available service computation. Relevant aspects of the model interrelated areas and implementation key points are also discussed.

A distributed admission control model for class-based networks using edge-toedge QoS and SLS monitoring

Lima, Solange; Carvalho, Paulo; Santos, Alexandre; Freitas, Vasco
Fonte: IEEE Press Publicador: IEEE Press
Tipo: Conferência ou Objeto de Conferência
Publicado em /11/2002 Português
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The advent of class-based networks has brought new needs for network traffic control in order to assure a certain QoS level. Despite the existing proposals, achieving a generic admission control (AC) strategy for traffic entering these networks is still an open issue. This paper provides new insights on how AC shall be accomplished proposing an encompassing AC model for multi-service class-based networks, which covers both intra-domain and end-to-end operation, without requiring changes in the network core and complex AC signaling. For each service type, AC is distributed and based on both on-line edge-to-edge monitoring of relevant QoS parameters and SLSs utilization. Service monitoring, performed at egress nodes, provides adequate metrics to ingress nodes which take implicit or explicit AC decisions based on service-dependent criteria. Although being oriented to flow AC, the model can easily be applied to SLS AC. SLS auditing and SLS traffic conditioning are tasks also covered.

Handling concurrent admission control in multiservice IP networks

Lima, Solange; Carvalho, Paulo; Freitas, Vasco
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em /01/2006 Português
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Comunicação apresentada na "Consumer Communications & Networkin Conference 2006", Las Vegas, Nevada, USA, 8-10 Janeiro 2006.; This paper debates the problem of handling concurrent admission control decisions in multiservice networks, putting forward solutions to mitigate the negative impact that distributed admission of flows might have on the service level guarantees provided to network customers. Keeping in mind that simplicity is a key factor for deployable solutions, we suggest and discuss the use of (i) a service-dependent concurrency index; (ii) a token-based system and (iii) a rate-based credit system, as alternative or complementary proposals to minimize or solve QoS degradation resulting from AC false acceptance.

Distributed admission control in multiservice IP networks : concurrency issues

Lima, Solange; Carvalho, Paulo; Freitas, Vasco
Fonte: Academy Publishers Publicador: Academy Publishers
Tipo: Artigo de Revista Científica
Publicado em /06/2006 Português
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In distributed admission control (AC) schemes, handling concurrent AC decisions assumes a relevant role in avoiding over or false acceptance and, consequently, service quality degradation. This problematic is even more intricate in multiservice network environments where distinct service levels need to be fulfilled. This paper debates and points out solutions to mitigate the negative impact that distributed admission of flows might have on the service level guarantees provided to network customers. Keeping in mind that simplicity is a key factor for deployable AC solutions, we suggest and discuss the use of (i) a service-dependent concurrency index; (ii) a token-based system and (iii) a rate-based credit system, as alternative or complementary proposals to minimize or solve QoS degradation resulting from AC false acceptance.

The role of admission control in assuring multiple services quality

Carvalho, Paulo; Lima, Solange; Freitas, Vasco
Fonte: IEEE Computer Society Publicador: IEEE Computer Society
Tipo: Conferência ou Objeto de Conferência
Publicado em /11/2006 Português
Relevância na Pesquisa
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Considering that network overprovisioning by itself is not always an attainable and everlasting solution, Admission Control (AC) mechanisms are recommended to keep network load controlled and assure the required service quality levels. This article debates the role of AC in multiservice IP networks, providing an overview and discussion of current and representative AC approaches, highlighting their main characteristics, pros and cons regarding the management of network services quality. In this debate, particular emphasis is given to an enhanced monitoring-based AC proposal for assuring multiple service levels in multiclass networks.; Centro de Ciências e Tecnologias da Computação do Departamento de Informática da Universidade do Minho (CCTC)

Adaptive admission control in a NGN service platform

Ferreira, André Filipe dos Santos; Carvalho, Paulo; Lima, Solange
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Artigo de Revista Científica
Publicado em /04/2010 Português
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http://wts2010.eng.usf.edu/; In NGN service-provisioning platforms the existence of an efficient and flexible admission control mechanism is essential for providing quality of service in a reliable and stable way, avoiding congestion scenarios caused by indiscriminate and uncontrolled service requests. The capability of modulating and regulating the rate of call acceptance, and provide service differentiation allow indirect control of the load submitted to the platform. This paper presents a service admission control solution that enables to differentiate, limit and modulate the rate by which service requests are submitted into a NGN service-provisioning platform. The solution is focused on providing a fair level of bandwidth sharing among service classes, in a configurable and dynamic way so that it can adapt the distribution by which service requests are served. To sustain the design goals of our solution, major scheduling disciplines and rate control mechanisms are here studied and compared in order to elect the more adequate components. The implemented solution was submitted to unit and charge tests; the results show its effectiveness and robustness in controlling and differentiating incoming service calls.

A service-oriented admission control strategy for class-based IP networks

Lima, Solange; Carvalho, Paulo; Freitas, Vasco
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em /04/2008 Português
Relevância na Pesquisa
67.17774%
The clear trend toward the integration of current and emerging applications and services in the Internet launches new demands on service deployment and management. Distributed service-oriented traffic control mechanisms, operating with minimum impact on network performance, assume a crucial role as regards controlling services quality and network resources transparently and efficiently. In this paper, we describe and specify a lightweight distributed admission control (AC) model based on per-class monitoring feedback for ensuring the quality of distinct service levels in multiclass and multidomain environments. The model design, covering explicit and implicit AC, exhibits relevant properties that allow managing quality of service (QoS) and service-level specifications (SLSs) in multiservice IP networks in a flexible and scalable manner. These properties, stemming from the way service-dependent AC and on-line service performance monitoring are proposed and articulated in the model’s architecture and operation, allow a self-adaptive service and resource management, while abstracting from network core complexity and heterogeneity. A proof of concept is provided to illustrate the AC criteria ability in satisfying multiple service class commitments efficiently. The obtained results show that the self-adaptive behavior inherent to on-line measurement-based service management...

Adaptive admission control in real-time systems

Ferreira, André Filipe dos Santos; Lima, Solange
Fonte: Instituto Superior Técnico (IST) Publicador: Instituto Superior Técnico (IST)
Tipo: Artigo de Revista Científica
Publicado em //2009 Português
Relevância na Pesquisa
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In real-time service provisioning platforms the existence of an efficient and flexible admission control mechanism is essential for providing quality of service in a reliable and stable way, avoiding congestion scenarios caused by indiscriminate and uncontrolled service request admission. The capability of modeling and regulating the rate of call acceptance, and provide service differentiation allow indirect control of the load submitted to the platform. This paper presents a service differentiated admission control solution that allows to limit and modulate the rate by which service requests are submitted into a service provisioning platform. The solution is focused on providing a fair level of bandwidth sharing among service classes, in a configurable and dynamic way so that it can adapt the distribution by which service requests are served. To sustain the design decisions of our solution, major scheduling disciplines and rate control mechanisms, some of them proposed recently, are studied and compared. The solution was submitted to unit and charge tests, whose results show its effectiveness and robustness.

Marginal productivity index policies for problems of admission control and routing to parallel queues with delay

Jacko, Peter; Niño-Mora, José
Fonte: Universidade Carlos III de Madrid Publicador: Universidade Carlos III de Madrid
Tipo: Trabalho em Andamento Formato: application/pdf
Publicado em /12/2008 Português
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In this paper we consider the problem of admission control of Bernoulli arrivals to a buffer with geometric server, in which the controller’s actions take effect one period after the actual change in the queue length. An optimal policy in terms of marginal productivity indices (MPI) is derived for this problem under the following three performance objectives: (i) minimization of the expected total discounted sum of holding costs and rejection costs, (ii) minimization of the expected time-average sum of holding costs and rejection costs, and (iii) maximization of the expected time-average number of job completions. Our employment of existing theoretical and algorithmic results on restless bandit indexation together with some new results yields a fast algorithm that computes the MPI for a queue with a buffer size of I performing only O(I) arithmetic operations. Such MPI values can be used both to immediately obtain the optimal thresholds for the admission control problem, and to design an index policy for the routing problem (with possible admission control) in the multi-queue system. Thus, this paper further addresses the problem of designing and computing a tractable heuristic policy for dynamic job admission control and/or routing in a discrete time Markovian model of parallel loss queues with one-period delayed state observation and/or action implementation...

E-diophantine: an admission control algorithm for WiMAX networks

Pérez-Costa, Xavier; Mezzavilla, Marco; Boisson de Marea, J. Roberto; Araúz, Julio
Fonte: IEEE Publicador: IEEE
Tipo: info:eu-repo/semantics/acceptedVersion; info:eu-repo/semantics/conferenceObject Formato: application/pdf
Publicado em 18/04/2010 Português
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Admission control algorithms must ensure that, when a new QoS resource reservation is accepted, reservations already present in the system continue having their QoS guarantees honored. In this paper we consider different approaches to compute the aggregated allocated capacity in WiMAX networks and, based on their limitations, propose the EDiophantine solution. The mathematical foundations for the designed approach are provided along with the performance improvements to be expected, both in accuracy and computational terms, as compared to three alternatives of increasing complexity. Finally, the different solutions considered are evaluated with OPNET’sWiMAX simulator in a realistic scenario.; European Community's Seventh Framework Program; Proceedings of: 2010 IEEE Wireless Communications and Networking Conference (WCNC 2010), 18-21 April 2010, Sydney, Australia

Cross-layer design of admission control policies in code division multiple access communications systems utilizing beamforming

Sheng, Wei
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado Formato: 580279 bytes; application/pdf
Português
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To meet growing demand for wireless access to multimedia traffic, future generations of wireless networks need to provide heterogenous services with high data rate and guaranteed quality-of-service (QoS). Many enabling technologies to ensure QoS have been investigated, including cross-layer admission control (AC), error control and congestion control. In this thesis, we study the cross-layer AC problem. While previous research focuses on single-antenna systems, which does not capitalize on the significant benefits provided by multiple antenna systems, in this thesis we investigate cross-layer AC policy for a code-division-multiple-access (CDMA) system with antenna arrays at the base station (BS). Automatic retransmission request (ARQ) schemes are also exploited to further improve the spectral efficiency. In the first part, a circuit-switched network is considered and an exact outage probability is developed, which is then employed to derive the optimal call admission control (CAC) policy by formulating a constrained semi-Markov decision process (SMDP). The derived optimal policy can maximize the system throughput with guaranteed QoS requirements in both physical and network layers. In the second part, a suboptimal low-complexity CAC policy is proposed based on an approximate power control feasibility condition (PCFC) and a reduced-outage-probability algorithm. Comparison between optimal and suboptimal CAC policies shows that the suboptimal CAC policy can significantly reduce the computational complexity at a cost of degraded performance. In the third part...

The Value of Service Rate Flexibility in an M/M/1 Queue with Admission Control

Dimitrakopoulos, Yiannis; Burnetas, Apostolos
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We consider a single server queueing system with admission control and the possibility to switch dynamically between a low and a high service rate, and examine the benefit of this service rate flexibility. We formulate a discounted Markov Decision Process model for the problem of joint admission and service control, and show that the optimal policy has a threshold structure for both controls. Regarding the benefit due to flexibility, we show that it is increasing in system congestion, and that its effect on the admission policy is to increase the admission threshold. We also derive a simple approximate condition between the admission reward and the relative cost of service rate increase, so that the service rate flexibility is beneficial. We finally show that the results extend to the expected average reward case.

Optimal Admission Control for Many-Server Systems with QED-Driven Revenues

Sanders, Jaron; Borst, S. C.; Janssen, A. J. E. M.; van Leeuwaarden, J. S. H.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/11/2014 Português
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We consider Markovian many-server systems with admission control operating in a QED regime, where the relative utilization approaches unity while the number of servers grows large, providing natural Economies-of-Scale. In order to determine the optimal admission control policy, we adopt a revenue maximization framework, and suppose that the revenue rate attains a maximum when no customers are waiting and no servers are idling. When the revenue function scales properly with the system size, we show that a nondegenerate optimization problem arises in the limit. Detailed analysis demonstrates that the revenue is maximized by nontrivial policies that bar customers from entering when the queue length exceeds a certain threshold of the order of the typical square-root level variation in the system occupancy. We identify a fundamental equation characterizing the optimal threshold, which we extensively leverage to provide broadly applicable upper/lower bounds for the optimal threshold, establish its monotonicity, and examine its asymptotic behavior, all for general revenue structures. For linear and exponential revenue structures, we present explicit expressions for the optimal threshold.; Comment: 36 pages, 7 figures

Performance Analysis of Connection Admission Control Scheme in IEEE 802.16 OFDMA Networks

Bouchti, Abdelali El; Kafhali, Said El; Haqiq, Abdelkrim
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 12/08/2013 Português
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IEEE 802.16 OFDMA (Orthogonal Frequency Division Multiple Access) technology has emerged as a promising technology for broadband access in a Wireless Metropolitan Area Network (WMAN) environment. In this paper, we address the problem of queueing theoretic performance modeling and analysis of OFDMA under broad-band wireless networks. We consider a single-cell IEEE 802.16 environment in which the base station allocates subchannels to the subscriber stations in its coverage area. The subchannels allocated to a subscriber station are shared by multiple connections at that subscriber station. To ensure the Quality of Service (QoS) performances, a Connection Admission Control (CAC) scheme is considered at a subscriber station. A queueing analytical framework for these admission control schemes is presented considering OFDMA-based transmission at the physical layer. Then, based on the queueing model, both the connection-level and the packet-level performances are studied and compared with their analogues in the case without CAC. The connection arrival is modeled by a Poisson process and the packet arrival for a connection by a two-state Markov Modulated Poisson Process (MMPP). We determine analytically and numerically different performance parameters...

Autonomous Vehicle Public Transportation System: Scheduling and Admission Control

Lam, Albert Y. S.; Leung, Yiu-Wing; Chu, Xiaowen
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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Technology of autonomous vehicles (AVs) is getting mature and many AVs will appear on the roads in the near future. AVs become connected with the support of various vehicular communication technologies and they possess high degree of control to respond to instantaneous situations cooperatively with high efficiency and flexibility. In this paper, we propose a new public transportation system based on AVs. It manages a fleet of AVs to accommodate transportation requests, offering point-to-point services with ride sharing. We focus on the two major problems of the system: scheduling and admission control. The former is to configure the most economical schedules and routes for the AVs to satisfy the admissible requests while the latter is to determine the set of admissible requests among all requests to produce maximum profit. The scheduling problem is formulated as a mixed-integer linear program and the admission control problem is cast as a bilevel optimization, which embeds the scheduling problem as the major constraint. By utilizing the analytical properties of the problem, we develop an effective genetic-algorithm-based method to tackle the admission control problem. We validate the performance of the algorithm with real-world transportation service data.; Comment: 16 pages...