The article is mainly to solve the security problems existing in ethernet passive optical network. The most obvious thing is that when optical network unit (ONU) is registered, to prevent attackers from eavesdropping and camouflage, we need mutual authentication between the optical line terminal and ONU to ensure the legality of both sides. To solve this problem, this paper designs a bidirectional authentication scheme based on number theory research unit signature algorithm (NTRUSign), using NTRUSign algorithm for authentication, can avoid impersonation attacks but could not prevent the middle eavesdropping attacks, so the data encryption algorithm AES using the traditional transmission of encrypted. Elliptic curve Diffie–Hellman algorithm is used to carry out key exchange, as the key to the subsequent data transmission, and can be completed in the ONU registration process without the need of third-party participation. The analysis results show that this method improves the reliability of identity authentication and data transmission security.
Identity-related security issues inherently present in passive optical networks (PON) still exist in the current (1G) and next-generation (10G) Ethernet-based passive optical network (EPON) systems. We propose a mutual authentication scheme that integrates an NTRUsign digital signature algorithm with inherent multipoint control protocol (MPCP) frames over an EPON system between the optical line terminal (OLT) and optical network unit (ONU). Here, a primitive NTRUsign algorithm is significantly modified through the use of a new perturbation so that it can be effectively used for simultaneously completing signature and authentication functions on the OLT and the ONU sides. Also, in order to transmit their individual sensitive messages, which include public key, signature, and random value and so forth, to each other, we redefine three unique frames according to MPCP format frame. These generated messages can be added into the frames and delivered to each other, allowing the OLT and the ONU to go ahead with a mutual identity authentication process to verify their legal identities. Our simulation results show that this proposed scheme performs very well in resisting security attacks and has low influence on the registration efficiency to to-be-registered ONUs. A performance comparison with traditional authentication algorithms is also presented. To the best of our knowledge, no detailed design of mutual authentication in EPON can be found in the literature up to now.
A photonic crystal fiber (PCF) with low confinement loss and nearly zero ultraflattened chromatic dispersion over ultra-broad wavelength is proposed. Some important PCF design parameters, such as the influences of the diameter of air holes and hole pitch on the confinement loss, chromatic dispersion has been thoroughly investigated by employing the full vectorial finite element method with anisotropic perfectly matched layers. The simulation results show that the dispersion coefficient is <0.6 ps/(km⋅nm) and is larger than −0.5 ps/(km⋅nm) from 1.32 to 1.64 μm, and the confinement losses are <10 −7 dB/m in the same wavelength range by introducing extra air holes in the same ring.
With the high-speeding development of the ultrashort laser pulses techniques, the stability of the soliton propagating in
the dispersion-shift fiber has been becoming the topic in high speed optical communication system. From the nonlinear
Schrödinger equation, in this paper we discuss a quasi soliton specific solution without distortion which has the stable
propagating property, then simulate the waveform about these quasi solitons numerically, and more, by modifying the
structure parameters of the fiber the width of these quasi soliton pulse can be adjusted and the soliton communication
system can be optimized finally.
A new approach combining a discrete iterative reconstruction-reprojection algorithm (DIRR) with a finite impulse response (FIR) low-pass filter is proposed for reconstructing images comprising opaque objects in optical computed tomography (CT). This filter, employing a rectangular window function and various bandwidths, is adopted to smooth the reprojection data between iterative reconstruction and reprojection stages. Compared reconstruction results of the traditional iterative reconstruction-reprojection (IRR) algorithm, projection space iteration reconstruction-reprojection (PSIRR) algorithm, and the new DIRR algorithm for an asymmetrical four-peak and a single-peak test image, including a circle round opaque object, are studied. The results show that the reconstruction precision of the new algorithm is related to the value of the bandwidth of the finite impulse response (FIR) filter, and the optimal bandwidth increases when the space frequency of the reconstructed image ascends. Furthermore, the DIRR algorithm with an optimal bandwidth has an obviously higher reconstruction precision than IRR and PSIRR algorithms, and has a potential application of reconstructing images, including obstacle objects with limited views.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.