Proposed Network System Research Articles

Throughput optimization in hybrid C-C+L-band elastic optical networks enabled by hybrid modulation and wavelength/modulation conversion

Elastic optical networks (EONs) have been proposed to address the increasing needs of future communications, yet the capacity of these networks is expected to run out. Evolving the current C-band system to use the C+L-band is a costly and time-consuming solution. This paper presents a stopgap solution to meet the increasing communication needs in the short term by exploiting hybrid fused C- and L-band transmission before the full evolution is achieved. The proposed physical-layer-impairments-aware high spectral efficiency (PAHSE) algorithm jointly applies time domain hybrid modulation (TDHM) and modulation and wavelength conversion techniques and uses accurate models to estimate physical layer impairments for the C- and C+L-band links. The hybrid network scheme converts C-band signals to L-band at the regenerator nodes, which increases the system throughput. The proposed PAHSE algorithm assigns the highest spectral efficiency to each transparent segment of each traffic request while satisfying the quality of transmission requirements. Simulations are conducted on two network topologies, one of large diameter and the other highly connected, using several types of traffic that mimic demands expected in future communication scenarios. Compared to the benchmark, the proposed network system and algorithm result in much higher network throughput, up to a 120% increase in the sum bit rate in the NSFNET-24 topology, thus obviating the urgent need for full C+L deployment.

Vision based Human Activity Recognition using Deep Neural Network Framework

Human Activity Recognition (HAR) has become a well-liked subject in study as of its broad application. With the growth of deep learning, novel thoughts have emerged to tackle HAR issues. One example is recognizing human behaviors without exposing a person's identify. Advanced computer vision approaches, on the other hand, are still thought to be potential development directions for constructing a human activity classification approach from a series of video frames. To solve this issue, a deep learning neural network technique using Depthwise Separable Convolution (DSC) with Bidirectional Long Short-Term Memory (DSC-BLSTM) is proposed here. The redeeming features of the proposed network system comprises a DSC convolution that helps to reduce not only the number of learnable parameters but also computational cost in together training and testing method The bidirectional LSTM process can combine the positive and the negative time direction. The proposed method comprises of three phases, which includes Video data preparation, Feature Extraction using Depthwise Separable Convolution Neural Network algorithm and DSC-BLSTM algorithm. The proposed DSC-BLSTM method obtains high accuracy, F1-score when compared to other HAR algorithms like MC-HF-SVM, Baseline LSTM Bidir-LSTM algorithms.

Edge-Based Hybrid System Implementation for Long-Range Safety and Healthcare IoT Applications

In many conventional Internet-of-Things (IoT) applications, data are transferred directly from the sensor network to the cloud via a gateway for further data processing. However, this typical usage of a gateway is not suitable for every application. For short-range IoT wireless protocols [e.g., Bluetooth low energy (BLE)], multiple gateways are required to achieve broader coverage, which is inconvenient. In this article, an edge-based hybrid network system architecture is presented. The proposed system consists of hybrid routers and an IoT gateway. The router supports two wireless protocols, BLE and long range (LoRa), and is equipped with a solar energy harvester to extend the router's lifetime. It can extend the coverage of short-range BLE network by utilizing LoRa wireless technology, and support fundamental edge computing tasks such as preliminary data processing. The IoT gateway can support multiple IoT protocols, including LoRa, BLE, and XBee. It can perform more advanced edge computing tasks, such as data filtering, storage, processing, user interface, and cloud connection. Three case studies incorporating a wearable safety monitoring sensor network, a healthcare monitoring application, and a smart hospital application are studied with the proposed edge network system to demonstrate its promising capabilities to support IoT applications. Experimental evaluations indicate that by processing data at the edge, the minimal delay is only 11.5 ms. Furthermore, with the hybrid LoRa network implementation, the BLE network can be extended to 2.4 km.

Performance Enhancement and Capacity Enlargement for a DWDM-PON System Utilizing an Optimized Cross Seeding Rayleigh Backscattering Design

In this work, a record of 16 channels, with future channel spacing in the telecommunication standardization sector of the International Telecommunications Union G.694.1 (ITU-T G.694.1) for Dense Wavelength Division Multiplexing (DWDM) (i.e., 12.5 GHz), is simulated and tested. This work is done to realize a proposed high capacity DWDM-Passive Optical Network (DWDM-PON) system. These specifications are associated with enhancing the upstream (US) capacity to 2.5 Gb/s over a 25 km Single-Mode Fiber (SMF) transmission and producing a noteworthy average Bit Error Rate (BER) of 10−12 during the system’s evaluation process. These performance indicators are achieved through design optimization of the cross-seeding Rayleigh Backscattering (RB) elimination technique. This optimization has successfully reduced (compared to the cross-seeding related literature) the simulated DWDM-PON components and maintained an effective Rayleigh Backscattering elimination with the aforementioned system’s performance enhancement and capacity enlargement.

Radio Over Fiber-Based Wavelength Division Multiplexed/Time Division Multiplexed Passive Optical Network Architecture Employing Mutual Injection Locked Fabry-Perot Laser Diodes

Abstract We demonstrate a radio-over-fiber-based hybrid wavelength-division-multiplexed/time division multiplexed passive optical network (PON) to transmit 5 Gbps data rate to serve 32 subscribers. A broadband light source (BLS) is realized by mutual injection locking between two Fabry-Perot laser diodes at the transmission section to seed wavelength-division-multiplexed channels. Mutual injection locking technique is used to enhance the performance over single Fabry-Perot laser diode and 15 dB/Hz improvements in relative intensity noise(RIN) is realized in our proposed network system. All-optical up-conversion of a 10-GHz 1.25 Gbps on off keying radio frequency (RF) signal is achieved using one single-arm Mach-Zehnder modulator (MZM). Transmission performance over 25-km single mode fiber is investigated. Low bit error rate with enhanced eye-diagram is obtained in our proposed system. As a result, the radio over fiber (ROF)-based wavelength-division-multiplexed/time division multiplexed PON set up employing mutually injection locked Fabry-Perot laser diodes can be a better choice in high speed long-haul optical communication system.

A Smart Congestion Control Mechanism for the Green IoT Sensor-Enabled Information-Centric Networking.

Information-Centric Networking (ICN) is a new Internet architecture design, which is considered as the global-scale Future Internet (FI) paradigm. Though ICN offers considerable benefits over the existing IP-based Internet architecture, its practical deployment in real life still has many challenges, especially in the case of high congestion and limited power in a sensor enabled-network for the Internet of Things (IoT) era. In this paper, we propose a smart congestion control mechanism to diminish the network congestion rate, reduce sensor power consumptions, and enhance the network performance of ICN at the same time to realize a complete green and efficient ICN-based sensor networking model. The proposed network system uses the chunk-by-chunk aggregated packets according to the content popularity to diminish the number of exchanged packets needed for data transmission. We also design the sensor power-based cache management strategy, and an adaptive Markov-based sensor scheduling policy with selective sensing algorithm to further maximize power savings for the sensors. The evaluation results using ndnSIM (a widely-used ICN simulator) show that the proposed model can provide higher network performance efficiency with lower energy consumption for the future Internet by achieving higher throughput with higher cache hit rate and lower Interest packet drop rate as we increase the number of IoT sensors in ICN.

BRAINsens: Body-Worn Reconfigurable Architecture of Integrated Network Sensors

Body sensor network (BSN) is a promising human-centric technology to monitor neurophysiological data. We propose a fully-reconfigurable architecture that addresses the major challenges of a heterogenous BSN, such as scalabiliy, modularity and flexibility in deployment. Existing BSNs especially with Electroencephalogarm (EEG) have these limitations mainly due to the use of driven-right-leg (DRL) circuit. We address these limitations by custom-designing DRL-less EEG smart sensing nodes (SSN) for modular and spatially distributed systems. Each single-channel EEG SSN with a input-referred noise of 0.82 μVrms and CMRR of 70dB (at 60Hz), samples brain signals at 512 sps. SSNs in the network can be configured at the time of deployment and can process information locally to significantly reduce data payload of the network. A Control Command Node (CCN) initializes, synchronizes, periodically scans for the available SSNs in the network, aggregates their data and sends it wirelessly to a paired device at a baud rate of 115.2kbps. At the given settings of the I2C bus speed of 100kbps, CCN can configure up to 39 EEG SSNs in a lego-like platform. The temporal and frequency-domain performance of the designed "DRL-less" EEG SSNs is evaluated against a research-grade Neuroscan and consumer-grade Emotiv EPOC EEG. The results show that the proposed network system with wearable EEG can be deployed in situ for continuous brain signal recording in real-life scenarios. The proposed system can also seamlessly incorporate other physiological SSNs for ECG, HRV, temperature etc. along with EEG within the same topology.

On-Demand Routing and Spectrum Allocation for Energy-Efficient AoD Nodes in SDM-EONs

Elastic optical networks (EONs) and space-division multiplexing (SDM) are promising technologies for future core optical networks with high transmission capacity. Traditional optical node architectures for SDM-EONs have two important problems: flexibility and power consumption. Architecture on demand (AoD) is a new concept for an optical node architecture, and an optical node based on this concept is called an AoD node. AoD nodes can be dynamically constructed according to the traffic request by interconnecting input/output ports and building modules with optical switches. Although AoD nodes have great flexibility, power consumption is still a serious problem for them. In this paper, we propose an energy-efficient network system that includes a novel energy-efficient AoD node architecture and resource assignment method cooperating with this node architecture. The proposed system solves the power-consumption problem by simplifying the implemented building modules based on spatial multiplicity of SDM-EONs. The proposed on-demand routing and spectrum allocation method efficiently satisfies the restricted spectrum arrangement that is required by energy-efficient AoD nodes. Finally, we evaluate the proposed system of node architecture and resource allocation method through computer simulations. The simulations show that the proposed network system can improve both the power consumption and the blocking probability of path setup requests in the entire network.

Bidirectional and simultaneous transmission of baseband and wireless signals over RSOA based WDM radio-over-fiber passive optical network using incoherent light injection technique

Reflective semiconductor optical amplifier (RSOA) based wavelength division multiplexed radio-over-fiber passive optical network (WDM−RoF−PON) has been proposed and demonstrated, to transmit 2.5Gbps baseband (BB) and 1.25Gbps wireless data in downstream and 1Gbps BB data signal in upstream over 25-km single-mode fiber (SMF), and wireless downstream signal over 25-km SMF as well as 5.2m free space in air. In the downstream, 2.5Gbps BB data and 1.25Gbps wireless data are modulated using single-electrode Mach–Zehnder modulator (SD-MZM) based on double-sideband with optical carrier suppression (DSBCS) scheme and simultaneously transmitted by incoherent light injection technique and employing fiber Bragg grating (FBG) at the base station. RSOA is utilized at the user end to reuse the carrier for uplink transmission. High receiver sensitivity, low bit-error-rate (BER) and excellent eye-diagram, eye height are achieved in our proposed network system and the results affirm the acceptability of proposed RSOA based WDM−RoF−PON.

High capacity hybrid WDM/TDM-PON employing fiber-to-the-home for triple-play services with 128 ONUs

A hybrid wavelength division multiplexing/time division multiplexing passive optical network (WDM/TDM) PON employing fiber-to-the-home (FTTH) for triple play services with 128 optical network units has been proposed and demonstrated, to transmit data, voice and video services simultaneously. 10 Gbps differential phase shift keying signal is employed to symbolize the internet and voice component. The radio frequency (RF) and sub carrier multiplexing scheme are utilized to comprehend analog video services. The multiplexed RF and data signal is modulated by external LiNbO3 phase modulator to mitigate chromatic dispersion and to obtain a small power penalty in receiver. The results show that FTTH triple play services can be successfully transmitted over a distance of 50 km with low transmission power penalties and better receiver sensitivity. High Q-factor, low bit-error-rate and excellent eye-diagram are achieved in our proposed network system and the results affirm the acceptability of proposed high capacity radio over fiber based hybrid WDM/TDM-PON.

A Wireless On-line Temperature Monitoring System for Rotating Electrical Machine

Wireless communication can be a useful method to monitor the electrical machine as it provides the main characteristics of online signal processing. Our contribution in this current paper consists in studying a new system to monitor the rotating electrical machines based on wireless communication. The main objective of this system is to detect the temperature value of the squirrel cage induction machine’s rotor, using the IEEE 802.11 protocol. However, the application of wireless communication inside the rotating electrical machines is not self-evident due to the fact that the electromagnetic compatibility problems between devices isn’t obviously guaranteed. So, in order to obtain a good reliability for wireless communication, the study of the electromagnetic field inside rotating electrical machine is essential. As a first step in this paper, we are going to focus mainly on the flux effect of the rotating electrical machine through the finite element method which offers so much information on the phenomena characterizing the electrical machine operation. This method proves that the high frequency domain transmitter won’t be disturbed by the low frequency existing flux inside the machine. As a second step in this study, the proposed network system design is presented. Then, the communication protocol, the hardware design based on the transmitting chip Roving Networks (RN-171) as well as the software design are illustrated. Finally, the experimental results of the proposed system are investigated to validate its feasibility.

Optimization strategy for air traffic flow in multi-airport network

To avoid the airport congestion and reduce flight delays, the paper studied the airport traffic balance from a system perspective at the strategic level. By considering the single-airport approach and departure as well as the correlation between the multi-airport connecting flights, the paper proposed network system on traffic flow which is open and has a direction in multi-airport; the paper set up multi-airport open network assignment model which was based on constraint capacity and multiple connecting flights and which minimized the total delay of all flights in the network within the target. The model was simulated which combined on the three major airports’ actual flight data in domestic. Simulation results show that: the proposed model can coordinate and optimize the matching of multi-airport network traffic and capacity. It also can minimize the system’s delayed flights based on using of system capacity; the paper can deploy optimization strategy in traffic flow for air traffic control sector and provide supporting decision-making basis for the civil aviation department of the flight plan. Key words: Air traffic flow management, multi-airport, assignment, optimization.

MRSVP: a resource reservation protocol for an integrated services network with mobile hosts

This paper describes a reservation protocol to provide real-time services to mobile users in an Integrated Services Packet Network. Mobility of hosts has significant impact on the quality of service provided to a real-time application. The currently proposed network system architecture and mechanisms to provide real-time services to fixed hosts are inadequate to accommodate the mobile hosts which can frequently change their point of attachments to the fixed network. Mobile hosts may experience wide variations of quality of service due to mobility. To reduce the impacts of mobility on QoS guarantees, a mobile host needs to make advance resource reservations at multiple locations it may possibly visit during the lifetime of the connection. The currently proposed reservation protocol in the Internet, RSVP, is not adequate to make such reservations for mobile hosts. In this paper, we describe a new reservation protocol, MRSVP, for supporting integrated services in a network with mobile hosts.

Studies on the threatened woody perennial taxa in the flora of Egypt I. Protected areas of Egypt: New proposals

AbstractThe World Conservation Strategy recognize two types of protection: in situ and ex situ preservations. A network of protected areas should be established to safeguard a nation's living resources. The first list of nature reserves in Egypt included 12 sites to be protected ares across the country.On the conservation action, the authors propose a series of conservation sites to the proposed network system of preservations. Selection of sites is mainly based on the plant species criteria that help in identifying areas that deserve urgent protection. The series include seven nature reserves, six wildlife sanctuaries and five botanic gardens.