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Wissam Fawaz - One of the best experts on this subject based on the ideXlab platform.

  • Improved EDF-based management of the Setup of Connections in opaque and transparent optical networks
    Photonic Network Communications, 2014
    Co-Authors: Wissam Fawaz
    Abstract:

    The need to support the diverse quality-of-service (QoS) requirements of the ever-emerging Internet applications is a major challenge for optical network operators. This paper tackles such a challenge through the definition of a QoS-aware optical Connection Setup management scheme. The proposed scheme utilizes the Earliest Deadline First (EDF) queueing discipline to schedule the Setup of optical Connections that cannot be established due to lack of optical resources. The EDF-based approach aims at minimizing blocking probability while realizing QoS differentiation. Blocking probability reduction is realized through the insertion of blocked Connection requests into a queue giving them thus a second chance with respect to network access. QoS differentiation on the other hand is achieved as follows. The blocked Connection requests are ranked in the EDF queue according to their Connection Setup requirements, which are viewed as deadlines during Connection Setup. In this way, pending Connection requests having shorter Setup time requirements are guaranteed to experience better QoS compared to the ones having longer Setup time requirements. The performance of the EDF-based strategy is analyzed through extensive simulations in the context of both opaque and transparent NSFNET network topologies. The reported results show that the proposed strategy yields remarkable reduction in terms of blocking probability while effecting QoS differentiation.

  • DICTAP (2) - A Novel Event-Driven QoS-Aware Connection Setup Management Scheme for Optical Networks
    Communications in Computer and Information Science, 2011
    Co-Authors: Wissam Fawaz, Abdelghani Sinno, Raghed Bardan, Maurice Khabbaz
    Abstract:

    This paper proposes a QoS-Aware Optical Connection Setup Management scheme that uses the Earliest Deadline First (EDF) queueing discipline to schedule the Setup of the optical Connections. The benefits of this EDF-based scheme are twofold: a) it reduces the blocking probability since blocked Connection requests due to resource unavailability are queued for possible future Setup opportunities and b) it realizes QoS differentiation by ranking the blocked requests in the EDF queue according to their Connection Setup time requirements, which are viewed as deadlines during Connection provisioning. As such, pending lesser delay-tolerant requests are guaranteed to experience better QoS than the ones having longer Setup time requirements. Extensive simulations are performed to gauge the merits of the proposed EDF-based scheme and study its performance in the context of two network scenarios, namely, the National Science Foundation Network (NSFNET) and the European Optical Network (EON).

  • Preemption-Enabled Setup of Optical Connections Coupled with Event-Driven Rerouting
    IEEE Communications Letters, 2011
    Co-Authors: Wissam Fawaz, Zahi Nakad, Maroun Aad
    Abstract:

    In an era of uncertain business tendencies, realizing profitable optical networks is emerging as the most urgent task for optical operators. This task is aggravated by the need to support quality of service (QoS) differentiation, especially with the continuous development of new applications, each having different QoS requirements. This letter proposes to tackle these challenges through the definition of a novel QoS-aware Connection Setup strategy. The proposed Setup approach enables network operators to ensure both efficient utilization of network resources and Connection blocking probability differentiation. Resource efficiency is achieved via event-driven rerouting, whereas differentiated blocking probability is realized by preemption. Specifically, high priority Connections are equipped with the capability of preempting lower priority Connections, which through event-driven rerouting experience smaller blocking probability. Performance of this novel Connection Setup strategy is analyzed in this letter by simulating its operation in the context of the National Science Foundation Network (NSFNET). The obtained simulation results show that the proposed strategy can minimize the overall blocking probability while achieving QoS differentiation.

  • Deadline-based Connection Setup in wavelength-routed WDM networks
    Computer Networks, 2010
    Co-Authors: Wissam Fawaz, Iyad Ouaiss, Ken Chen, Harry G. Perros
    Abstract:

    This article addresses the ubiquitous topic of quality of service (QoS) aware Connection provisioning in wavelength-routed WDM optical networks. The impact of the Connection Setup time of an optical Connection has not been adequately addressed in the open literature. As such, this paper presents a novel approach that uses the optical Connection Setup time as a service differentiator during Connection provisioning. The proposed approach utilizes the Earliest Deadline First (EDF) queueing algorithm to achieve deadline-based Connection Setup management with the deadline being the Setup time requirement of an optical Connection. The proposed EDF-based approach would allow the network operator to improve the QoS perceived by the end clients. Performance of this novel scheme is analyzed by accurately calculating various parameters, such as the fraction of Connections provisioned on-time (i.e. prior to deadline expiration) and the average time it takes to successfully Setup a Connection. In addition, the presented approach is validated by a simulation that analyzes the performance of the proposed Connection Setup scheme in the specific context of the National Science Foundation Network (NSFNET). The obtained results show that a deadline-based Setup strategy can minimize blocking probability while achieving QoS differentiation.

  • ICC - A Simple Quality-of-Service-Based Connection Setup Management Approach for Optical Networks
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: Wissam Fawaz, Ken Chen, Zahi Nakad, Chadi Abou-rjeily
    Abstract:

    One of the major challenges for optical network operators is related to realizing profitable networks that preserve the overall satisfaction of their end customers. This necessitates ensuring a controlled network resource usage while decreasing Connection blocking probability. However, optical networks are witnessing the introduction of an increasing number of new services, each having different requirements. As such, the evolution towards resource efficient Connection Setup management strategies that provide differentiated call-blocking probability becomes inevitable. Building on the previous observation, we propose in this paper a novel Connection Setup management strategy. This latter aims to differentiate the blocking probability among different classes of lightpath requests, while avoiding the starvation of the lower class lightpaths. The main idea behind our proposal is to privilige higher class lightpaths via preemption and to protect the lower class lightpaths through rerouting. In this manner, the proposed strategy serves the double objective of minimizing the overall Connection blocking probability and of realizing quality of service (QoS) differentiation. The previous claim is asserted through our simulation results that gauge the main benefits behind our proposed Connection Setup strategy. The simulation results drawn from the National Science Foundation Network (NSFNET) and the European Optical Network (EON) show that the proposed strategy achieves both differentiated and low blocking probabilities.

Xiaohua Jia - One of the best experts on this subject based on the ideXlab platform.

  • A distributed routing and wavelength assignment algorithm for real-time multicast in WDM networks
    Computer Communications, 2002
    Co-Authors: Chuanhe Huang, Xiaohua Jia, Yongbing Zhang
    Abstract:

    Routing and wavelength assignment for online real-time multicast Connection Setup is a difficult task due to the dynamic change of availabilities of wavelengths and the consideration of wavelength conversion delay in wavelength division multiplexing (WDM) networks. This paper presents a distributed routing and wavelength assignment scheme for the Setup of real-time multicast Connections. It integrates routing and wavelength assignment as a single process, which greatly reduces the Connection Setup time. The proposed routing method is based on the Prim's minimum spanning tree (MST) algorithm and the K-restricted breadth-first search method, which can produce a sub-minimal cost tree under a given delay bound. The wavelength assignment uses the least-conversion and load balancing strategies.

  • An integrated routing and admission control mechanism for real‐time multicast Connection establishment
    International Journal of Communication Systems, 2001
    Co-Authors: Xiaohua Jia, Yongbing Zhang, Niki Pissinou, S. A. M. Makki
    Abstract:

    There are two major difficulties in real-time multicast Connection Setup. One is the design of an efficient distributed routing algorithm which optimizes the network cost of routing trees under the real-time constraints. The other is the integration of routing with admission control into one single phase of operations. This paper presents a real-time multicast Connection Setup mechanism, which integrates multicast routing with real-time admission control. The proposed mechanism performs the real-time admission tests on a cost optimal tree (COT) and a shortest path tree (SPT) in parallel, aiming at optimizing network cost of the routing tree under real-time constraints. It has the following important features: (1) it is fully distributed; (2) it achieves sub-optimal network cost of routing trees; (3) it takes less time and less network messages for a Connection Setup. Copyright © 2001 John Wiley & Sons, Ltd.

  • An integrated routing and admission control mechanism for real-time multicast Connections in ATM networks
    IEEE Transactions on Communications, 2001
    Co-Authors: Xiaohua Jia, Wei Zhao
    Abstract:

    This letter presents: 1) a delay analysis model, which is specially for the admission control of real-time multicast Connections in ATM networks; 2) a distributed multicast routing algorithm, which generates suboptimal routing trees under real-time constraints; and 3) a Connection Setup method that integrates multicast routing with admission control.

  • A distributed routing and wavelength assignment algorithm for real-time multicast in WDM networks
    2001 International Conferences on Info-Tech and Info-Net. Proceedings (Cat. No.01EX479), 1
    Co-Authors: Chuanhe Huang, Xinmeng Chen, Xiaohua Jia
    Abstract:

    Routing and wavelength assignment for online real-time multicast Connection Setup is difficult due to the dynamic change of availabilities of wavelengths on links and the consideration of wavelength conversion delay in WDM networks. This paper presents a distributed routing and wavelength assignment algorithm for the Setup of real-time multicast Connections. It integrates routing and wavelength assignment as a single process, which greatly reduces the Connection Setup fine. The multicast routing algorithm is based on Prim's MST (minimum spanning tree) algorithm and K-restricted breadth-first search method, which can produce a subminimal cost tree under a given delay bound. The wavelength assignment uses least-conversion and load balancing strategies.

  • ICCCN - An efficient admission control method of real-time multicast Connections in wide area networks
    Proceedings 7th International Conference on Computer Communications and Networks (Cat. No.98EX226), 1
    Co-Authors: Xiaohua Jia, Yongbing Zhang, Niki Pissinou, Kia Makki
    Abstract:

    There are two major difficulties in real-time multicast Connection Setup. One is the design of an efficient distributed routing algorithm which optimizes the network cost of routing trees under the real-time constraints. The other is the integration of routing with admission control into one single phase of operations. This paper presents a real-time multicast Connection Setup mechanism, which integrates multicast routing with real-time admission control. The proposed mechanism performs the real-time admission tests on a COT (cost optimal tree) and a SPT (shortest path tree) in parallel, aiming at optimizing network cost of the routing tree under real-time constraints. It has the following important features: (1) it is fully distributed; (2) it achieves sub-optimal network cost of routing trees; (3) it takes less time and less network messages for a Connection Setup.

Chadi Abou-rjeily - One of the best experts on this subject based on the ideXlab platform.

  • ICC - A Simple Quality-of-Service-Based Connection Setup Management Approach for Optical Networks
    2008 IEEE International Conference on Communications, 2008
    Co-Authors: Wissam Fawaz, Ken Chen, Zahi Nakad, Chadi Abou-rjeily
    Abstract:

    One of the major challenges for optical network operators is related to realizing profitable networks that preserve the overall satisfaction of their end customers. This necessitates ensuring a controlled network resource usage while decreasing Connection blocking probability. However, optical networks are witnessing the introduction of an increasing number of new services, each having different requirements. As such, the evolution towards resource efficient Connection Setup management strategies that provide differentiated call-blocking probability becomes inevitable. Building on the previous observation, we propose in this paper a novel Connection Setup management strategy. This latter aims to differentiate the blocking probability among different classes of lightpath requests, while avoiding the starvation of the lower class lightpaths. The main idea behind our proposal is to privilige higher class lightpaths via preemption and to protect the lower class lightpaths through rerouting. In this manner, the proposed strategy serves the double objective of minimizing the overall Connection blocking probability and of realizing quality of service (QoS) differentiation. The previous claim is asserted through our simulation results that gauge the main benefits behind our proposed Connection Setup strategy. The simulation results drawn from the National Science Foundation Network (NSFNET) and the European Optical Network (EON) show that the proposed strategy achieves both differentiated and low blocking probabilities.

  • A novel Connection Setup management approach for optical wdm networks
    IEEE Communications Letters, 2007
    Co-Authors: Wissam Fawaz, Ken Chen, Chadi Abou-rjeily
    Abstract:

    Wavelength Division Multiplexing (WDM) has significantly increased the transmission capacity of today's optical networks. An increase in the available bandwidth is promoting at the same time the introduction of new services, each having different Quality of Service (QoS) requirements. In this regard, QoS parameters applicable to Connection Setup, namely Connection blocking probability and Connection Setup time, are expected to greatly influence the procedure of lightpath Setup. In view of this, we propose to consider the Connection Setup time requirement as a (timely increasing) priority indicator during optical Connection provisioning. In other words, we envisage in this letter the assignment of the highest Setup priority to those optical Connection requests having the shortest Setup time requirements. To achieve this purpose, we adapt the well known Earliest Deadline First (EDF) scheduling discipline to the particular case of optical Connection Setup management. In order to gauge the impact of our proposal on the QoS perceived by optical clients, we introduce in this letter a computational method. This latter is used for the assessment of the percentage of optical Connections that are successfully established under the proposed Setup management approach.

Gonzalo Camarillo - One of the best experts on this subject based on the ideXlab platform.

Wei Zhao - One of the best experts on this subject based on the ideXlab platform.