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The new technology of elastic optical network (EON) envisages a favorable solution for accommodating the heterogeneity of traffic over the future internet and to fulfill bandwidth-hungry requirement of today's world. Advance reservation (AR) is obligatory on initial-delay-tolerant services, like e-science and grid computing, that are having a remarkable involvement in next-generation internet traffic. In this paper, the authors proposed a routing and spectrum assignment (RSA) algorithm, which improves spectrum utilization by minimizing the blocking probability. This technique ensures spectrum availability for each connection request, but depending on the call arrival time and slot availability, there may be some delay and it is referred as spectrum allocation using reservation. The other proposed algorithm considers reservations based on prediction called as spectrum allocation using prediction and reservation. The simulation results show that the latter technique increases spectrum utilization even more and decreases call blocking compared to existing RSA algorithms. To the best of the author's knowledge, this is the first effort of spectrum assignment using prediction and reservation. [ABSTRACT FROM AUTHOR]

In recent days vehicular ad-hoc networks find its extensive applications by broadcast transmissions. Vehicle to vehicle communication provide better results by avoiding the major problems in the road such as the collision of vehicles, better route selection during congestion, fuel consumption etc. In this paper we present a collision avoidance based protocol. The collision of transmitting data can be avoided using medium access control (MAC) protocol. We have assessed and analyzed the performance of the proposed routing protocol Vehicular Ad-hoc on-demand Distance Vector (VAODV), which is a modification of Ad-hoc On-demand Distance Vector (AODV) routing protocol. We have analysed the performance of the proposed VAODV protocol through simulation results and latter extended for OSPF ensuring high reliability. [ABSTRACT FROM AUTHOR]

A new disintegrated channelization approach for the backward pumped nonlinear distributed Raman amplifier is proposed by enacting the differential coupled equations of Raman amplification, in fiber, trailing by the solution of NLSE using the first integral method first time to the best of our knowledge. A nonlinear channel modeling-based simulation is adapted for the approximation of the Raman gain profile. To realize the real-time dynamic system, 16 multiplexed channels of prime C-band are employed in a QPSK/NRZ modulation environment with a 100 Gbps bit rate for optical network reconfiguration. A non-uniform gain is reported while the disparity in BER is observed from 10−12 to 10−8. [ABSTRACT FROM AUTHOR]

We have investigated the theoretical and principal analysis of cascaded electroabsorption modulators (EAMs) and Mach-Zehnder modulator (MZM). We have proposed a technique to generate an ultraflat and power efficient optical frequency comb (OFC) by the serial cascading of two EAMs and one single-drive MZM. Continuous wave (CW) light source is modulated and spectrum broadened by two EAMs and MZM, respectively. Here, EAMs in cascaded mode produce ultrashort pulses followed by MZM, which is introduced to perform intensity modulation and tuned the power variation of even and odd order sidebands at the same level for obtaining a flat optical spectrum at the output. The first EAM acts as a subcarrier generator and the latter one acts as a subcarrier enhancer, which is followed by the MZM acting as subcarrier flatter. By this proposed technique, we have generated 63 subcarriers with 10-GHz spacing and within 2-dB power fluctuation. The generated OFC has a bandwidth of 630 GHz. This technique generates OFC with an appreciable power level and flattened optical spectrum, which is very much essential in dense wavelength division multiplexing and elastic optical networks. [ABSTRACT FROM AUTHOR]

Traditional dense wavelength division multiplexing (DWDM) technology is no longer enough to meet the extensive growth in the demand of bandwidth in an efficient and effective manner under the fixed grid environment. Thus, a technology is needed to overcome the challenges raised by the ever-increasing demand of bandwidth in an effective manner with efficient utilization of spectral resources. To solve this problem, an elastic optical network (EON) paradigm comes into existence. It uses a flexible grid technology that removes the limitations of fixed grid DWDM technology and increases the channel capacity to meet current bandwidth demand with proper utilization of optical spectrum. We present the evolution of EON from the DWDM network. We have discussed the main components and characteristics of EON that includes superchannel and sliceable bandwidth variable transponder (SBVT). Thereafter, we discuss the different modulation and transmission techniques used in EON. Next, we present the recently proposed architectures of SBVT followed by its applications. Lastly, we have discussed various subcarrier generation techniques in brief. [ABSTRACT FROM AUTHOR]

• An advanced deep learning model is proposed to predict the quality of transmission (QoT) (Q-factor, chromatic dispersion) of a light-path. • The proposed model was tested on a data-set that contains data extracted from Microsoft's optical backbone network in North America. • The performance of the proposed model is compared with reference approaches viz; SVM, MLP, NN, and LSTM to show if such models could be considered for predicting the estimated received Q-factor and chromatic dispersion of established light-paths. • Results exhibit that the proposed model achieves the best performance across multiple channels of this data-set and even in a case when the size of the training data-set is small. Increasing traffic demand in the backbone optical network urges the initiation of new solutions that allow an increment in the transmission/network capacity without a considerable rise in service costs. To attain this objective, simpler and quicker network reconfiguration processes is required. A significant issue intrinsically correlated with network reconfiguration is the quality of transmission (QoT) (BER, SNR, Q-factor, chromatic dispersion and polarization mode dispersion) estimation. Predicting the QoT of already established light-paths enable network operators to respond proactively to performance deterioration, which helps in enhancing or sustaining quality of service (QoS). Recently, several deep learning-based approaches have been presented to estimate the QoT of an optical network. This paper proposes an advanced deep learning model comprising a long short-term memory (LSTM) network along with three fully connected layers that leverage the transmission quality metrics collected from the network's control plane to predict QoT of light-path. The three additional fully connected layers help the model learn the more complex patterns in the data that a basic LSTM cannot learn on its own and improve the model's performance by three orders of magnitude. Moreover, the proposed model doesn't require a large data-set to provide high accuracy results, which decreases the control plane's load. Our model was tested on a data-set that contains data extracted from Microsoft's optical backbone network in North America. We compare the performance of the proposed model with reference approaches viz; SVM, MLP, NN, and LSTM to show if such models could be considered for predicting the estimated received Q-factor and chromatic dispersion of established light-paths. Results exhibit that the proposed model achieves the best performance across multiple channels of this data-set and even in a case when the size of the training data-set is small. The proposed model provides high prediction accuracy, which is perfect for the next-generation agile optical network. [ABSTRACT FROM AUTHOR]

In this article, the proposed Distributed Raman Amplifier (DRA) simulator is designed on the MATLAB Simulink platform. 16 channels DWDM in C-band (1544–1559 nm) and 32 channels CWDM system in S-, C- and L band (1460–1625 nm) are executed with data rate of 100 Gb/s. The designed standalone system realizes the various effects that may arise at the receiver output due to reconfiguration of channels in real-time dynamic WDM optical traffic. Gain excursion assessment, and bit error rate (BER) are investigated for 200 km long Fiber cable and 45 km of Raman amplifier in co-pumping, counter pumping and bidirectional pumping propagation. [ABSTRACT FROM AUTHOR]

A novel Step Size based Recursive least squares- Least mean fourth(SSRL) adaptive algorithm is proposed as a noise canceller, in this paper, to eliminate the Ocular artifacts(OAs) from the recorded raw EEG signals. Here, both second and fourth-order power optimization algorithms have been used to eliminate the OAs from raw EEG signals. The Reference signals, such as vertical Electrooculogram and horizontal Electrooculogram signals, have been recorded separately.FIR filter has been used to process the reference signals by updating filter coefficients using the proposed SSRL algorithm. Thereby, true EEG signals are obtained by subtracting the processed signals from the raw signals. Moreover, a mathematical model for the mean square deviation analysis is proposed for the SSRL algorithm, which provides better results compared to the conventional methods. [ABSTRACT FROM AUTHOR]

An Elastic or flexible-grid Optical Network (EON) is an emerging technology for efficient resource utilization. In this paper, a Weight distributed service provisioning (WDSP) algorithm for routing and spectrum assignment (RSA) based on a request for a connection is proposed. This novel technique for spectrum allocation based on the demands of the connection request reduces the blocking of connections due to improper spectrum assignment. The connection requests are classified into two categories based on demand: small and large connection requests. The smaller size connection requests are assigned to the lower index slots, and the larger size connection requests are assigned to the highest index slots. By implementing this approach, a relatively large number of connection requests can be handled via the availability of a large set of contiguous slots. The simulation results illustrate that the proposed algorithm is relatively more efficient due to enhanced blocking performance; effective spectrum efficiency can be achieved. [ABSTRACT FROM AUTHOR]

• Direct intensity modulation based edge filter detection technique is proposed. • The proposed technique increases system performance of weight measurement system. • It increases the sensitivity and resolution of the system up to two times. • The proposed technique can be integrated with any EFD interrogation system. Fiber Bragg Gratings (FBGs) are extensively used as strain and temperature sensors in various industrial applications. The key task for FBG based sensing system is to convert the optical sensing data into user friendly information that can be interpreted with ease. Edge filter detection (EFD) interrogation technique is commonly used to convert wavelength encoded sensing data into optical power variation. This technique is simple and cost effective as compared to other interrogation technique. While using FBG as both edge filter and sensing element the sensitivity of the system depends upon the slope of its reflection or transmission spectrum. Therefore, there is always a tradeoff between sensitivity and measurement range in this interrogation technique. Direct Intensity Modulation (D-IM) based EFD is proposed in this manuscript, where a tunable laser source is modulated using different message signals and is tuned in the linear region of FBG transmission spectrum. This technique observes the change in amplitude of message signal at the photodetector output due to shift in Bragg wavelength. Later the proposed technique is utilized in optical load cell based weight measurement system to observe the system performance. Maximum sensitivity of 196.7 mV/kg and SNR of 63 dB is obtained by using the proposed technique. Decrease in percent error with enhancement in system resolution is observed, as compared to previously reported conventional EFD technique based optical weight measurement. The proposed technique has shown significant improvement in system performance with nominal increase in system complexity that makes this technique more effective for industrial applications. [ABSTRACT FROM AUTHOR]

Tremendous growth of traffic in Vehicular Ad hoc NETworks (VANET) in recent days leads into enormous delay in data transfer. To overcome this, we use Software Defined Vehicular Networks (SDVN) as a promising solution with reliable multi-hop cooperative data dissemination (MHCDD) for data traffic forwarding in the network of end to end connectivity. In SDN based system, data forwarding in a road side unit is through cooperatively data dissemination. The intermittent connectivity in VANET dynamically changes because of the vehicular mobility, thereby causing SDN and RSU controller to link/connection failures. However, in multi-hop data traffic forwarding from source to destination node through RSU and SDN switches in which controllers control the data traffic for Virtual Network Customization (VNC). In this paper, we introduce Software defined-VANETs (SD-VANETs) to improve the network resource utilization by providing the network connectivity for dynamic network topology. Here, we analyze the network model using M/M/1 and M/M/m queueing models, which are proposed to effectively minimize the delay and enhance the throughput in multi-server queueing system of the SDVN. To achieve this, we propose a novel solution with enhancement of the SDVN system reliability in terms of service rate which is based on service level agreement. [ABSTRACT FROM AUTHOR]