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Physical layer cryptography offers the unique possibility of certifiably secure data transmission between remote locations. We present here for the first time, to our knowledge, the experimental results of a secure full Poincare occupancy polarization encrypted data transmission system. The scheme uses an approach to macroscopic physical layer cryptography based on combining a multilevel polarisation...
Plug and play optical (PPO) nodes may be used to facilitate the deployment of optical networks. PPO nodes must be able to learn about the signal propagation properties of the surrounding optical fibers and make their wavelength routing decisions based on the collected data. This paper discusses what are the open challenges that must be overcome to provide cost effective and performing ad hoc networking...
The cost of a network with a routing is defined as a sum of arc costs that depend on the capacity only. The capacity corresponds to the number of paths of the routing that traverse the arc. We sketch some simple observations that may give insight in the partial order among possible network designs
A relatively new optimization criterion in studies of optical networks is that of minimizing the total number of ADMs. In these networks each given lightpath uses one ADM device at each of its two endpoints, and it is assigned a color, so that at most g lightpaths of the same color can share an edge. Lightpaths of the same color that share an endpoint can use a common ADM at that endpoint. We discuss...
In optical networks that are based on provisioned or switched lambda-paths there is no support for sub-lambda granularity, and therefore, the network is not efficient for carrying demands of bandwidth requirement significantly smaller than the capacity of a lambda-path. Even if we add a layer over the lambda-layer to improve granularity and also add grooming capability the network will not be efficiently...
Along with GMPLS new network survivability issues arose, and new models and tools were needed to cope with them. In this context the notion of Shared Risk Resource Group have been proposed, and then the colored graph model to answer these needs. In this work the basic definitions about colored graphs are reminded. Then the question of the transformation of a multilayer network into a colored graph...
A new calculation method to estimate path availability under dual failure scenarios for networks designed for 100% restorability against single span failures is presented. This method is applicable to all survivability schemes and considers their respective restoration or protection effect. A case study calculates the availability of all service paths within a long haul network under four protection/restoration...
This paper presents the analytic results of comparison of mode transformation in 2D time-varying photonic structures on examples of plane waveguide and circular whispering gallery mode (WGM) resonator. The situation is that a natural mode propagates inside the structure at the moment when the refractive index changes abruptly in time inside it. The basic interest is to gain insight into details of...
In the present report principal optical properties, of semiconducting large-sized nanocrystalline (LSNC) (with thickness within 10-50 nm) are presented. A quantitative parameter for description of the LSNC state is introduced. Influence of the surrounding polymer matrices on the properties of the LSNC is shown. Role of the surrounding polymer matrix background in the manifestation of the optoelectronic...
Ever since Pendry's paper on perfect lens the idea of near field subwavelength imaging has been a driving force in the rapid development of the field of metamaterials as the search for suitable structures capable of near field imaging continues. A large variety of physical mechanisms were suggested to be responsible for near field imaging, ranging from excitation of surface plasmon-polariton resonances...
Microstructured fibers with periodically modulated diameter are proposed for controlling supercontinuum generation. We report the results of numerical study of spectral broadening of low-order femtosecond solitons. It is shown that periodical modulation of phase-matching conditions leads to spectrum broadening and disappearing of spectral gap between spectra of soliton and dispersive wave. The structure...
Summary form only given: In contrast to analysis techniques of microstructured fibres, which have already started being tackled efficiently, the available design methods are still incipient. In general, real inverse design procedures involve an optimization algorithm to carry out the minimization of a certain merit function. In this contribution we present a differential algorithm to design photonic...
Summary form only given: In this study two new sub-classes of photonic bandgap materials, a) curvilinear-lattice photonic crystals, whose distinctive feature is that their individual scatterers are arranged in a curvilinear lattice and b) variable size photonic bandgap structures are introduced. We show that adhering to some restrictions in the acceptable lattice transformations; one can achieve omnidirectional...
This study aims to develop a computer program for the simulation of light propagation in microstructured fibres in the linear regime, and then including nonlinearities. Simulation results in the nonlinear case is presented for the investigation of photonic crystal fibre-based wavelength converter
The research activity presented is focused on the study of numerical methods for electromagnetism and the development of simulation codes for integrated and fiber optics devices. The theoretical approach is mainly based on the finite element method (FEM). The developed codes permit both modal and propagative general-purpose analysis, suitable for the study of structures with arbitrary geometry, distribution...
This paper presents a switch based on a liquid crystal filled photonic bandgap fiber (PBF) where the signal light is transmitted in the transverse direction. A broad and smooth operational wavelength range can be obtained with this type of optical switch
In this paper a new GMPLS controlled optical Ethernet network architecture is proposed, where the GMPLS capable Ethernet switches equipped with tunable laser modules have full control over the wavelengths taken through the underlying dynamic optical core network. This future network architecture has main advantages providing high bandwidth, flexible and cost effective metro Ethernet services. The...
Contention resolution is one of the most significant concerns in OBS networks. As an important contention resolution approach, segmentation can pass packets using as much as possible fragmented resources. Aiming at using bandwidth as efficiently as possible, we propose a new segmentation-base contention resolution scheme-random dropping. When contention occurs, any part of a contending burst could...
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