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... network. B. Effectiveness of partial reconfiguration with TM Estimation We first compare the average squared errors of traffic matrix estimation between existing estimation method called tomogravity =-=[15]-=- and our method. Fig. 3 shows the results, where we set the threshold Nr to be 1, 3 and 5. From this figure, we can observe that our method can decrease the estimation error dramatically compared to t...

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... 1, go to Step 1. Otherwise, go to End. End Then, at each stage, after the new VNT is determined, the routes of packets over the VNT is calculated by using CSPF (Constraint-based Shortest Path First) =-=[12]-=- so as to make maximum link utilizations under TH . The detail of the heuristic algorithm is described as follows. 1) Optical path addition phase: If the link utilization of an optical path exceeds TH...

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...stigated the performance of existing TE methods in conjunction with estimated traffic matrices, and revealed that existing TE methods are less robust and do not work properly due to estimation errors =-=[9]-=-, [10]. We thus develop a practical VNT reconfiguration method for optical networks with taking traffic matrix estimation into consideration. According to [10], the full reconfiguration approach, whic...

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...l by X̄′n and ΔĀ′n, respectively. Finally, we use X̄′n = ΔĀ ′ nT, (5) instead of Eq. (2). To estimate the traffic matrix T̂ from Eq. (5), we apply the pseudo-inverse calculation method described in =-=[13]-=-. The traffic matrix T̂ is obtained from T̂ = pinv(Ān)X̄n, (6) where pinv(Ān) is the pseudo-inverse of matrix Ān. If we simply apply [13] to calculate the pseudo-inverse of Ān, some entries in T̂ ...

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...Section 4. II. PARTIAL RECONFIGURATION METHOD WITH TRAFFIC MATRIX ESTIMATION A. Design Principle and Method Overview We assume that the routes and VNT are calculated by PCE (Path Computation Element) =-=[11]-=-. A PCE first gathers the network information and estimate the traffic matrix by our estimation method. Then, PCE calculates the VNT and routes for the next stage by using the estimated traffic matrix...

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...ted the performance of existing TE methods in conjunction with estimated traffic matrices, and revealed that existing TE methods are less robust and do not work properly due to estimation errors [9], =-=[10]-=-. We thus develop a practical VNT reconfiguration method for optical networks with taking traffic matrix estimation into consideration. According to [10], the full reconfiguration approach, which comp...