Nguyen Van Nhan creator Poompat Saengudomlert Chairperson Teerapat Sanguankotchakorn Examination Committee Rajatheva, R.M.A.P Examination Committee Electricity of Vietnam (EVN) Scholarship donor text series technical report th Pathum Thani, Thailand Asian Institute of Technology 2010 continuing eng 64 leaves : ill. To increase the efficiency and decrease the cost of WDM networks,one important approach is optimization of optical amplifier placement. Considering the traffic change in the networkin terms of a given set of traffic matrices for different times of day, this thesis exploresseveral methods to find the minimum number ofamplifiers and their associated locations in metropolitan WDM rings. In order to handle thetraffic changes, we consider two methods tosolve the optimization problem: using a combinedtraffic matrixand using multiple sets of constraints. The procedure to solve each optimization problem includes routing andwavelength assignment (RWA) and linear approximation of non-linear constraints. The amplifier placement problem is formulated as a mixed integer linear programming (MILP) problem in unidirectional and bidirectional WDM rings. In addition, we consider the self-healing property of bidirectional WDM rings in case of a single link failure. Numerical results from optimization are obtained using the commercial software CPLEX. Compared to previous works on optical amplifier placement in metropolitan WDM rings, this thesis provides additional procedures to take into account traffic changes as well as the bidirectionalityin RWA. A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Telecommunications, School of Engineering and Technology Thesis (M.Eng.) - Asian Institute of Technology, 2010 Wavelength division multiplexing Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B04079 http://203.159.5.9/ait-thesis/detail.php?q=B04079 110219 20260817162218.0