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Adaptability of an effective access network in optical code division multiple access domain requires an efficient coding scheme which has the abilitiy to provide required communication capacity in terms of cardinality, reach, and data rates. In this paper, an extensive study and investigation has been carried out for adaptability study of a well-known coding scheme diagonal eigenvalue unity (DEU) code at various date rates in passive optical network (PON) environment. DEU code design is based on Jordan block matrix with ideal in-phase cross correlation (IPCC) properties. The numerical and simulation results show the ability of DEU code in supporting synchronized transmissions at different data rates that suits triple play services of video, audio and data (VAD). An algorithm is developed to determine the required chip duration that matches a particular service. It shows that data rate is more influential than code length on pulse duration especially for video applications. In support of the proposed algorithm, 5 Gb/s, 2.5 Gb/s, and 1.25 Gb/s data rate transmissions have been validated for various simultaneous users. In addition, a Poisson's distribution analysis is carried out aiming to study different bit rate scenarios with ad hoc population network. Results have concluded that higher value of average rate of simultaneous users (σ) is preferable for low data rate whereas the lower value of σ is suitable to the higher data rates in accordance with network population. In particular, for video streaming, the traffic running in a continuous fashion requires the highest transmission priority and small value of σ. [ABSTRACT FROM AUTHOR]

The advent of the Internet of Things (IoT) has enabled millions of potential new uses for consumers and businesses. However, with these new uses emerge some of the more pronounced risks in the connected object domain. Finite fields play a crucial role in many public-key cryptographic algorithms (PKCs), which are used extensively for the security and privacy of IoT devices, consumer electronic equipment, and software systems. Given that inversion is the most sensitive and costly finite field arithmetic operation in PKCs, this paper proposes a new, fast, constant-time inverter over prime fields F p based on the traditional Binary Extended Euclidean (BEE) algorithm. A modified BEE algorithm (MBEEA) resistant to simple power analysis attacks (SPA) is presented, and the design performance area-delay over F p is explored. Furthermore, the BEE algorithm, modular addition, and subtraction are revisited to optimize and balance the MBEEA signal flow and resource utilization efficiency. The proposed MBEEA architecture was implemented and tested on Xilinx FPGA Virtex #5, #6, and #7 devices. Our implementation over F p (length of p = 256 bits) with 2035 slices achieved one modular inversion in only 1.12 μs on Virtex-7. Finally, we conducted a thorough comparison and performance analysis to demonstrate that the proposed design outperforms the competing designs, i.e., has a lower area-delay product (ADP) than the reported inverters. [ABSTRACT FROM AUTHOR]

One dimensional encoding in optical communications has limitations in terms of the number of supported users and large bandwidth consumption. This study presents a new algorithm to generate two-dimensional (2D) encoding utilizing permutation vectors (PV) theory for incoherent multiple access network to suppress multiple access interference (MAI) and system complexity. The proposed code design approach is based on spectral/spatial techniques for code generation. All possible combinations of PV code-sets are obtained by utilizing all permutations of the vectors with the repetition of each vector weight (W) times. Furthermore, the 2D-PV code-set is constructed by combining two code sequences of the 1D-PV code. Furthermore, the transmitter–receiver architecture of the 2D-PV spectral/spatial (S/S) code based OCDMA system is presented. The Gaussian approximation is used to analyze the performance of the proposed OCDMA system with 2D- PV code by considering various noise sources (shot, thermal, and PIIN). Results indicate that the 2D-PV code provides increased cardinality by eliminating phase induced intensity noise (PIIN) effects with a minimum likelihood of interference between multiple user data. Simulation implementations validate the proposed system performance for an agreeable bit error rate (BER) of 10–9 [ABSTRACT FROM AUTHOR]

This paper presents design and implementation of a new two-dimensional fixed right shifting (2D-FRS) code in optical code-division multiple access (OCDMA) systems. The proposed code employs spatial domain in combination with spectral encoding to elevate orthogonality between the adjacent codes. In comparison with the existing 2D coding schemes, 2D-FRS not only reserves the multiple interference-cancellation property, but also provides better performance against the effects of shot, thermal and phase-induced intensity noise. Investigation of the proposed system using numerical and simulation approach shows that larger number of simultaneous users can be supported by 2D-FRS system in comparison with existing counterparts under given bit-error-rate (BER). This paper further examines the effect of dispersion on performance of 2D-FRS based OCDMA system due to the use of numerous fiber strands between the transmitter and receiver modules for spatial encoding operation. Investigation is made in terms of data rate, fiber span and channel spacing. Analysis using a highly recognized software called OPTISYSTEM verifies that the proposed system is able to support data rates of up to 32 × 1 Gbps without employing dispersion compensation fibers (DCFs). It is also shown that application of DCF can further negate MAI and support higher transmission capacity leading to a tradeoff between the limited dispersion effects and the MAI. If g = 0 ∩ h ≠ 0 and h = 0 ∩ g ≠ 0, hence R I (1)(g , h) and R I (2)(g , h) have nonzero value. This can be used to remove the effect caused by A g,h with g = 0 ∩ h ≠ 0 and g ≠ 0 ∩ h from R I (0)(g , h). Deducting Eqs. (7) and (8) from Eq. (6), Eq. (9) is attained as follows [ABSTRACT FROM AUTHOR]

Highlight • Development of a new 2D-FRS code. • Gaussian approximation is used to analyze performance analysis of 2D-FRS system. • Simulation validation of 2D-FRS numerical model. • Power saving feature at 2D-FRS receiver. • Accommodation of large number of active users with high bit rate. Abstract In this paper a new algorithm to generate two dimensional fixed right shifting (2D-FRS) code sequences is proposed, which is based on spectral/spatial incoherent OCDMA system. The proposed 2D-FRS algorithm is designed using 1D-FRS code with minimum cross correlation (MCC). The 2D-FRS codes enhance the system cardinality and offer elimination capability of MCC and its associated phase induced intensity noise (PIIN). Furthermore, the proposed algorithm allows multiple users with different code sequences to transmit data with minimum likelihood of interference. The architecture of transmitter-receiver structure of spectral/spatial 2D-FRS OCDMA system is presented. Gaussian approximation is used to analyze performance of the proposed 2D-FRS OCDMA system by investigating noise sources at photodiodes (PDs). It is shown that PD-1 and PD-3 have lower contribution in terms of noise power as compared to PD-0 and PD-2 due to division operation in MCC elimination process at the balanced detectors. Simulation results also validates the proposed system for an agreeable bit error rate (BER) of 10−9. It is observed that the 2-D FRS OCDMA system can support a higher number of users in deterministic and stochastic methods compared to the reported techniques such as Diagonal Eigenvalue Unity (DEU) and Two-Dimensional Diluted Perfect Difference codes (2D-DPD codes). The 2D-FRS cardinality surpassing the 2D-DPD and 2D-DEU by ≈71.21% and ≈9.09% respectively at the BER of 10−9. At 622 Mbits/s transmission data rate, the 2-D FRS meets the optical transmission requirements with lowest effective transmitted source power (P sr), −27.5 dBm in comparison to published codes. [ABSTRACT FROM AUTHOR]

• Development of new SSM families. • A configurable transmitter–receiver structure using S S M SSM code to support QoS. • High and Low QoS diversity are offered based on user choices. • Accommodation of large number of active users with high bit rate. This paper proposes a new coding scheme for spectral amplitude coding (SAC) family, known as Sigma Shift Matrix (SSM). Two techniques are proposed for the design of SSM coding scheme. The first technique combines the identity and upper shift matrices to form an SSM coding matrix named as SSM I. The second approach adapts the assembly of a single – entry, lower and upper shift matrices to compose another SSM matrix called SSM s. Combination of these matrices generates variable SSM code families, which can provide more flexibility in code weight selection and the number of users respectively. Furthermore, a modified SSM (MSSM) coding scheme is proposed through bitwise ANDing of SSM I and SSM S to further elevate performance of the proposed setup. The optimized structure of SSM coding scheme eliminates the influence of multiple access interference (MAI) and alleviate the effect of phase induced intensity noise (PIIN). Numerical results show that MSSM, SSM I and S S M S SSM S outperform the existing coding schemes in descending order and proves to be an efficient candidate for the implementation of high capacity next generation of optical communication networks. [ABSTRACT FROM AUTHOR]

In this paper, we present a new algorithm to generate two-dimensional (2D) permutation vectors' (PV) code for incoherent optical code division multiple access (OCDMA) system to suppress multiple access interference (MAI) and system complexity. The proposed code design approach is based on wavelength-hopping time-spreading (WHTS) technique for code generation. All possible combinations of PV code sets were attained by employing all permutations of the vectors with repetition of each vector weight (W) times. Further, 2D-PV code set was constructed by combining two code sequences of the 1D-PV code. The transmitter-receiver architecture of 2D-PV code-based WHTS OCDMA system is presented. Results indicated that the 2D-PV code provides increased cardinality by eliminating phase-induced intensity noise (PIIN) effects and multiple user data can be transmitted with minimum likelihood of interference. Simulation results validated the proposed system for an agreeable bit error rate (BER) of 10−9. [ABSTRACT FROM AUTHOR]

This paper presents high attitude platform Free space optics (HAP-FSO) channels using various filtering operations for fifth generation (5G) system. Performance analysis is done utilizing different types of optical filters such as Bessel, Trapezoidal, Gaussian and Rectangular. A comparison is carried out between our proposed scheme and reported counterpart. HAP-FSO performances have been investigated to be taken into account the effects of different factors such as transmission distance, transmitting aperture diameter, beam divergence, transmitter aperture diameter, and receiver diameter. Simulation analysis is performed in highly recognized software tool called Optisystem™ to validate the implementation and performance of the proposed system. It is found that the most extreme quality calculation can be accomplished via utilizing Gaussian optical channel in comparison with distinctive optical channels. In particular, with increasing data rate up to 5G coverage range application, minimum BER value is increased for all type of filters. But the trapezoidal filter achieved better results compared with other types of filters. [ABSTRACT FROM AUTHOR]

A new variable weight zero cross correlation code (VZCC) is designed that support different class of services in spectral encoding for OCDMA scheme. The proposed code has many benefits, such as the easy and strong mathematical way of code construction, acceptable code length, variable ZCC. A transmitter–receiver structure of the VZCC OCDMA system is presented. The performance of the proposed VZCC OCDMA system with noise sources at the direct detection scheme is studied using gaussian approximation. It is observed that the VZCC OCDMA scheme is able to accommodate more users in contrast to the reported techniques having a privilege of triple play services. For BER 10–9 the Modified Double Weight (MDW), Modified Quadratic Congruence (MQC), Modified Frequency Hopping (MFH), Hadamard, and VZCC supports 68, 70, 62, 18, and 145 users, respectively at − 10 dBm power. [ABSTRACT FROM AUTHOR]

Merging two coherent and incoherent optical sources: continuous wave light amplification by stimulated emission of radiations (CW LASER) and light emitting diode (LED) despite the difference in their physical nature from each other could be an efficient approach to expand a highly occupied network while trading-off the cost. In this paper, an efficient SAC-OCDMA system based on coherent and incoherent optical sources (CCIS) is designed. To evaluate CCIS design, fixed right shifting (FRS) code is adopted. FRS is built by utilizing specific type of Jordan matrices with direct algebraic procedures with minimum cross correlation (MCC). Additionally, an MCC elimination process would be more efficiency and can be seen in supporting large number of users. A quantitative comparison between SAC-OCDMA system using LED, CW laser sources and CCIS design is presented. Compared to LED sources, a CCIS design increases the number of supported users by almost three time while a reduction in number of optical sources is obtained by ≈ 50%. As compared to CW Laser sources, a CCIS design shows a reduction in number of optical sources by almost 50% while a lessening in number of supported users by ≈ 21%. A 22.6% cost saving per user is achieved for CCIS design over CW laser for nearly similar performance. It concludes that, CCIS design can provide a good solution for optical communication system. [ABSTRACT FROM AUTHOR]

In this paper the K-Nearest Neighbor (KNN) model which is one of machine learning (ML) algorithm is applied to distinguish between the four distinct Hermite Gaussian (HG) beams (HG00, HG01, HG02, and HG03) in mode division multiplexed (MDM)-free space optics (FSO) communication system. First, the performance of the FSO system using these different HG beams is investigated for rainy weather conditions in various Indian cities having distinct geographical locations. Transmission performance is evaluated in terms of quality (Q)-factor, signal-to-noise ratio (SNR), bit error rate (BER), and eye diagrams. Then, the values of the BER for the different HG beams are applied to the KNN ML model as to classify between them. HG modes are used for capacity enhancement. Results indicate that 80 Gbps can be transmitted over 1000 m in Hyderabad, 800 m in Pune, 580 m in Chennai, and 475 m in Mumbai at log (BER) ~ 10 - 15 , Q-factor less than 8, and SNR ~ 10 dB. Additionally, the K-Nearest Neighbor (KNN) ML model shows 94% classification accuracy between four HG beams. [ABSTRACT FROM AUTHOR]

This paper optimizes the design of two-dimensional enhanced multi diagonal (2D-EMD) code and conventional spectral/spatial (SS) optical code division multiple access system architecture for large capacity at relatively low powers. The existing 2D-EMD coding scheme is optimized by reducing the weight and length of spatial code sequence to minimize power losses across the encoding and decoding arrangement. Moreover, a complete system architecture is developed by optimizing the structures of conventional 2D SS optical line terminal (OLT) and remote node (RN) racks to reduce the use to long span optical fibers between the central office and subscribers premises. The optimized system architecture is implemented as per passive optical network (PON) specification in Optisystem and analysis is performed using several pivotal performance parameters. It is observed that optimization of the 2D-EMD (2D-OEMD) coding algorithm elevates both transmission capacity and cardinality at received powers as low as of − 10 dBm. Moreover, the new OLT and RN racks significantly reduces the length and number of optical fibers between the OLT and receiver modules. Consequently, the optimized SS 2D-OEMD system can support 192 subscribers at 2 Gbps of data each over the span of 25 km single mode fiber. Consequently, the proposed architecture can be adapted for numerous application with high bandwidth requirement including next generation PON, back bone for free space optical and fifth generation communication systems. [ABSTRACT FROM AUTHOR]

This paper proposes the design of a novel two-dimensional enhanced multi-diagonal (2D-EMD) code along with the implementation of corresponding architecture for incoherent optical code division multiple access passive optical network (OCDMA-PON). The proposed algorithm is derived by using spatial coding as second dimension in the existing 1D-EMD code to elevate orthogonality within adjacent codes and minimize the interference of subscribers simultaneously accessing the medium. Performance of the proposed 2D-EMD OCDMA system is analyzed through Gaussian approximation and simulation analysis for an agreeable bit error rate (BER) of 10 - 9 . Analytic analysis shows that the proposed 2D-EMD OCDMA system support more subscribers in comparison with existing systems based on 2D diluted-perfect difference (2D-DPD) and diagonal eigenvalue unity (DEU) codes. Cardinality of the proposed setup surpasses 2D-DPD and 2D-DEU by 5 and 1.8 times for an acceptable BER of 10 - 9 . Moreover, the optimal communication requirement is satisfied by 2D-EMD system with lowest effective source power of - 27 dBm at 622 Mbps of data. Simulation analysis through a highly recognized software called Optisystem also validates the mathematical analysis and shows that the proposed system can accommodate large number of subscribers at high data rates. Both analytical and simulation analysis proves that the proposed system is able to support next generation PONs. [ABSTRACT FROM AUTHOR]

Performance of the non-coherent spectral amplitude coding optical code division multiple access (SAC-OCDMA) systems is primarily degraded by the presence of noise sources generated during the process of optical-to-electrical (O/E) conversion at the receiving photodiode (PD). Phase induced intensity noise (PIIN) is generated by limitations in the coding scheme that leads to the mixing of adjacent spectrum's commonly known as multiple access interference (MAI). While, shot and thermal noise sources are generated at PD during the conversion of signal from O/E domain for further processing. This paper investigates and compares the performance of two detection techniques with reference to the received power units and suppression of noise sources while recovering and decoding enhanced multi diagonal (EMD) code. Both techniques namely spectral direct detection (SDD) and single PD detection (SPD) use one PD for O/E conversion to reduce the effect of shot and thermal noise. Numerical analysis using Gaussian approximation shows that SPD technique provides better performance for an acceptable bit error rate (BER) of 10−9 as compared with SDD technique, due to maximum recovery of power units in the received spectrum. Simulation analysis through a highly recognized software called Optisystem also validates the mathematical formalism and shows the EMD and SPD based SAC-OCDMA system is able to support 64 subscribers communication simultaneously beyond 1 Gbps of data while −10 dBm power is maintained at the receiving PD. [ABSTRACT FROM AUTHOR]

In this paper, a novel high speed and efficient area optimal Ate pairing processor implementation over Barreto-Naehrig (BN) and Barreto-Lynn-Scott (BLS12) curves on field-programmable gate array (FPGA) is proposed. The optimal Ate pairing proposed design, based on two steps: Miller loop and final exponentiation, is specifically optimized for FPGA platforms. The Miller Loop and Final Exponentiation algorithms are optimized and modified for careful scheduling to avoid data dependency and to decrease the number of loops and number of temporary variables required for final exponentiation. Furthermore, suitable multiplier combining Toom-Cook and Karatsuba algorithms is proposed to execute the arithmetical computations needed in pairing architecture processor over F p .Therefore, an enhancement in terms of pairing computation speed-up and memory resources capacity management is achieved. In this paper, we select the new pairing parameters, especially that has to be used to ensure the 128-bit security level [1]. The proposed optimal Ate pairing architecture at 128 bits security level has been implemented on Xilinx FPGA Virtex6. Our processor implemented over BN curves achieves the highest reported speed together with the best reported area-time performance on Virtex6 (0.35 ms at 225 Mhz). Finally, for BN-446 and BN-638, the pairing proposed processor performances are estimated. [ABSTRACT FROM AUTHOR]

Given the increasing complexity of cryptographic devices, testing their security level against existing attacks requires a fast simulation environment. SystemC is a standard language that is widely used for the modeling and the verification of complex systems. It is a promising candidate in Electronic System Level (ESL) which allows models to reach higher simulation speed. Accordingly, the Advanced Encryption Standard (AES) is one of the most known block ciphers. It is widely used in various applications in order to secure the sensitive data. It is considered to be secure. Still, some issues lie in the used key and the S-Box. This paper presents a SystemC implementation of a chaos-based crypto-processor for the AES algorithm. The design of the proposed architecture is studied using the SystemC tools. The proposed correction approach exploits the chaos theory properties to cope with the defaulting parameters of the AES algorithm. Detailed experimental results are given in order to evaluate the security level and the performance criteria. In fact, the proposed crypto-system presents numerous interesting features, including a high security level, a pixel distributing uniformity, a sufficiently large key-space with improved key sensitivity, and an acceptable speed. [ABSTRACT FROM AUTHOR]

This paper introduces a novel free space optics (FSO) communication system for future-generation high-speed networks. The proposed system integrates orbital angular momentum (OAM) modes with an optical code division multiple access (OCDMA) technique. Two OAM beams are used ( L G 0 , 0 and L G 0 , 10 ), each of which is used for transmitting three independent channels. Each channel is assigned by fixed right shift (FRS) codes and carries 10 Gbps of information data. The performance of the proposed model is evaluated under different foggy and dust storm conditions. Furthermore, the performance of two cities with different geographical locations, Alexandria city in Egypt and Srinagar city in India, is investigated to demonstrate its ability to be implemented in future generations. Bit error rate (BER), eye diagrams, received optical power (ROP), and channel capacity are used for studying the performance of the proposed system. The observed simulation results show successful transmission of 60 Gbps overall capacity with the longest propagation FSO range for Alexandria city, which is 1400 m. Because dust storms have a large attenuation when compared to different foggy conditions, the proposed model had the shortest propagation range of 315 m under low dust (LD), 105 m under moderate dust (MD), and 40 m under heavy dust (HD). Furthermore, the cloudy weather conditions that affect Srinagar city, which is considered a hilly area, make our suggested model achieve 1000 m. [ABSTRACT FROM AUTHOR]

Exploitation of the spectral/spatial two dimensional optical code division multiple access (2D-OCDMA) systems in passive optical networks (PONs) is not explored extensively due to the fact spatial encoding requires deployment of multiple star couplers in the topology where each coupler is connected to different ends of either transmitter or receiver nodes. As a result, this scheme is not suitable for PON applications because it requires a significant increase in the amount of fiber deployment within the network along with the complexity of implementation to deploy the required star couplers. To deploy spectral/spatial OCDMA systems at PON and reduce the impact of fiber strands, this work proposes and investigates an optimized architecture of 2D-OCDMA for PONs based on enhanced multi-diagonal (EMD) code. Spectral/spatial encoding technique is used to develop 2D-EMD coding algorithm from the existing 1D-EMD scheme. This operation elevates orthogonality between the adjacent codes and supports high capacity through superior noise mitigation at the receiving end. A complete system architecture is developed and implemented in an excessively used software for optical networks implementation and analysis called Optisystem, for analysis under different performance parameters of PON. It is observed that the proposed system provides better performance in terms of transmission capacity, and cardinality, in comparison with existing 1D-EMD code and other 2D-OCDMA counterparts. Analysis shows that for an agreeable BER of 10 - 9 the proposed system can support 192 subscribers each communicating at 2 Gbps of data over 25 km single mode fiber. In terms of capital expenditure (CAPEX), four times cost saving per user is achieved for proposed architecture (PA) over conventional architecture (CA) for nearly similar performance. [ABSTRACT FROM AUTHOR]