• Submitter Login
    View Item 
    •   Bilkent Repository
    • University Library
    • Bilkent Theses
    • Theses - Department of Electrical and Electronics Engineering
    • Dept. of Electrical and Electronics Engineering - Master's degree
    • View Item
    •   Bilkent Repository
    • University Library
    • Bilkent Theses
    • Theses - Department of Electrical and Electronics Engineering
    • Dept. of Electrical and Electronics Engineering - Master's degree
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Stochastig modeling with continuous feedback markov fluid queues

    Thumbnail
    View/Open
    Full printable version (1.546Mb)
    Date Issued
    2014
    Author
    Yazıcı, Mehmet Akif
    Show full item record
    Please cite this item using this persistent URL
    http://hdl.handle.net/11693/30003
    Collections
    • Dept. of Electrical and Electronics Engineering - Master's degree [511]
    Advisor
    Akar, Nail
    Publisher
    Bilkent University
    Abstract
    Markov fluid queues (MFQ) are systems in which a continuous-time Markov chain determines the net rate into (or out of ) a buffer. We deal with continuous feedback MFQs (CFMFQ) for which the infinitesimal generator of the background process and the drifts in each state are allowed to depend on the buffer level through continuous functions. Explicit solutions of CFMFQs for a few special cases has been reported, but usually numerical methods are preferred. A numerically stable solution method based on ordered Schur decomposition is already known for multi-regime MFQs (MRMFQ). We propose a framework for approximating CFMFQs by MRMFQs via discretizing the buffer space. The parameters of the CFMFQ are approximated by piecewise constant functions. Then, the solution is obtained by block-tridiagonal LU decomposition for the related MRMFQ. Moreover, we describe a numerical method that enables us to solve large scale systems efficiently. We model basically two different stochastic systems with CFMFQs. The first is the workload-bounded MAP/PH/1 queue, to which the arrivals occur according to a workload-dependent MAP (Markovian Arrival Process), and the arriving job size distribution is phase-type. The jobs that would cause the buffer to overflow are rejected partially or completely. Also, the service speed is allowed to depend on the buffer level. As the second application, we model the horizon-based delayed reservation mechanism in Optical Burst Switching networks with or without fiber delay lines. We allow multiple traffic classes and the effect of offset-based and FDL-based differentiation among traffic classes in terms of burst blocking is investigated. Lastly, we propose a distributed algorithm for air-time fairness in multi-rate WLANs that overcomes the performance anomaly in IEEE 802.11 WLANs. We also give a stochastic model of the proposed model, and provide a novel and elaborate proof for its effectiveness. We also present an extensive simulation study.

    BİLKENT UNIVERSITY

    Copyright © Bilkent University - Library Technical Services | 06800 Bilkent, Ankara TURKEY
    If you have trouble accessing this page and need to request an alternate format, contact the webmaster. Phone: (312) 290 1771

    Contact Us | Send Feedback | Off-Campus Access
     

    Browse

    All of BilkentCommunities & CollectionsTitleAuthorAdvisorIssue DateSubjectTypeDepartmentThis CollectionTitleAuthorAdvisorIssue DateSubjectTypeDepartment

    My Account

    Submitter Login

    Statistics

    View Usage Statistics

    BİLKENT UNIVERSITY

    Copyright © Bilkent University - Library Technical Services | 06800 Bilkent, Ankara TURKEY
    If you have trouble accessing this page and need to request an alternate format, contact the webmaster. Phone: (312) 290 1771

    Contact Us | Send Feedback | Off-Campus Access