Browsing by Subject "Optical restoration"

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    Optical restoration at the wavelength-multiplex-section level in WDM mesh networks
    (Institute of Electrical and Electronics Engineers, 1998-09) Karasan, E.; Goldstein, E.
    In the presence of rapidly growing demand, long-haul multiwavelength lightwave networks face the increasingly critical task of not only transporting large traffic volumes, but also of restoring them in the event of failures. This may be naturally done in two distinct ways: by rerouting individual wavelengths (wavelength-paths), or by rerouting full bundles of multiplexed wavelengths (wavelength-multiplex sections). We here evaluate the prospects for restoration at the wavelength-multiplex-scction level in national-scale long-haul wavelength-division-multiplexed mesh networks. The approach is found to offer the potential of substantial economic benefits, given current transponder costs. These benefits will largely vanish, however, if transponder costs decline by an order of magnitude.
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    Subnetwork partitioning and section restoration in translucent optical networks
    (SPIE, 2003) Karasan, Ezhan; Arısoylu, M.
    We discuss the problem of designing translucent optical networks composed of restorable, transparent subnetworks interconnected via transponders. We formulate the problem of designing restorable subnetworks in translucent networks as an Integer Linear Programming (ILP) problem, where the subnetworks are determined subject to the constraints that each subnetwork satisfies size limitations and it is 2-connected. A greedy heuristic algorithm for the same problem is also proposed for planar network topologies. We propose section restoration for translucent networks where failed connections are rerouted inside the subnetwork which contains the failed link. The network design problem of determining working and restoration capacities with section restoration is formulated as an ILP problem. Numerical results show that section restoration generates fiber costs which are close to those with the path restoration technique for the mesh topologies used in this study. It is also shown that the number of transponders with the translucent optical network is substantially reduced compared to opaque networks.