Message Signs Research Articles

Performance Evaluation of Modulation Techniques in Li-Fi

Now days wireless communication is an essential replacement area and reflects enormous changes in day to day lives. Mobile communication, Digital Modulation is very much important for increasing the speed and capability of the wireless communication network. Now there is a growing technique called Li-Fi, which is wireless optical networking technology. The objective of the paper is describing the Li-Fi and its modulation techniques. Li-Fi uses Light Emitting Diodes (LED) for transmitting the data through illumination by changing the intensity which is quicker and offers security, higher bandwidth, efficiency, and avails. Li-Fi technology is replacement of radio frequency and also offers a high data rate, cost-effective. This will help to achieve a wireless communication with a better performance. It can apply to day to day activities and will adopt in devices in the future. In the future, Li-Fi can be several fields in traffic management, airlines, power plants and hazardous environment, underwater communications, giga speed technology, smart lighting, education system, disaster management and mobile connectivity. In the Digital modulation the message signal is in the digital type and, therefore, the carrier wave is in sinusoidal form. Li-FI have a unique modulation technique called single carrier techniques multi-carrier techniques and color modulation techniques. Modulation techniques are as On-Off keying, Pulse width Modulation, Pulse Amplitude Modulation, Orthogonal Frequency Division Modulation and alternative digital modulation technique are summarized. Simulation is the imitation of the operation of a real-world methodology. The act of simulating requires that a model be developed and simulates the operation of the system over time. This paper tends to analyze the single carrier modulation techniques such as BPSK, QAM, and also tends to provide information on digital modulation technique parameters as Bit Error Rate, and its Performance.

Secure Text Hiding Method in Image Processing using Enhanced MSB Technique

The data hiding is known as a procedure which is used to achieve composite signals by embedding message signals into the host picture. Data hiding approach represents a class of processes which are implemented for embedding data into different formats. In this approach, secret message occurs along with the secret information. The steganography is defined as a process through which information produced from one source can be concealed into other sources. This thesis work presents a novel methodology for image steganography. The tested result demonstrated that the proposed technique shows its supremacy in terms of PSNR and MSE. The PSNR value of proposed approach is increased up to 15 percent in comparison with earlier approach. In comparison with earlier approach, the MSE value of proposed algorithm is decreased up to 10 percent.

Leakage-resilient group signature: Definitions and constructions

Group signature scheme provides a way to sign messages without revealing identities of the authentic signers. To achieve such functionality and to avoid the abuse of its power, anonymity and traceability are two essential properties for group signature scheme. In traditional group signature schemes, however, these two security properties are based on the perfectly-secure storage of secret information. Unfortunately, defective implementation of a cryptosystem always exists, and therefore unexpected information leakage is inevitable. In reality, side-channel attacks allow an adversary breaks the security of the whole system by eavesdropping a portion of secret information. To tackle this issue, in our work we present the security models of leakage-resilient group signature in bounded leakage setting and furthermore, propose three new black-box constructions of leakage-resilient group signature based on the proposed security models.

Perivascular adipose tissue-derived extracellular vesicle miR-221-3p mediates vascular remodeling.

Adipose tissue-secreted extracellular vesicles (EVs) containing microRNAs (miRNAs) convey intercellular message signaling. The biogenesis of EV-miRNAs from perivascular adipose tissue (PVAT) and their roles in intercellular communication in response to obesity-associated inflammation have not yet been fully explored. By feeding mice a high-fat diet for 16 wk, we established obesity-associated, chronic low-grade inflammation in PVAT, characterized as hypertrophy of perivascular adipocytes, decreased adipogenesis, and proinflammatory macrophage infiltration. We show that PVAT-derived EVs and their encapsulated miRNAs can be taken up into vascular smooth muscle cells (VSMCs) in vivo and in vitro. miR-221-3p is one of the highly enriched miRNAs in obese PVAT and PVAT-derived EVs. Transfer and direct overexpression of miR-221-3p dramatically enhances VSMC proliferation and migration. Peroxisome proliferator-activated receptor γ coactivator 1α is identified as a miR-221-3p target in VSMC phenotypic modulation. Obese mice secrete abundant miRNA-containing EVs, evoking inflammatory responses in PVAT and vascular phenotypic switching in abdominal aorta of lean mice. Local delivery of miR-221-3p mimic in femoral artery causes vascular dysfunction by suppressing the contractile genes in the arterial wall. Our findings provide an EV-miR-221-3p-mediated mechanism by which PVAT triggers an early-stage vascular remodeling in the context of obesity-associated inflammation.-Li, X., Ballantyne, L. L., Yu, Y., Funk, C. D. Perivascular adipose tissue-derived extracellular vesicle miR-221-3p mediates vascular remodeling.

Collaborative cross-layer framework for handover decision in overlay networks

Up to date the vertical handover (VHO) management across heterogeneous wireless networks has received large attention in recent researches. Independent decisions on different protocol layers responding to the same event may lead to un-optimal operation during VHO over heterogeneous wireless networks. There is demand for solutions capable of managing handovers while ensuring sufficient Quality of Experience for running applications with low signaling overhead. However, user perception has not been handled intensively in context-aware decision algorithms when the Mobile Node undergoes handover. The proposed cross-layer decision framework integrates a set of Quality of Experience based decision-making modules to provide the ability for upper layers to adapt dynamically to fluctuating environmental conditions and optimize the access selection process using a unified signaling messages. This middleware solution manage the signaling coordination actions based on feedback triggers and various policies to reduce false handover indications, compensate for link-layer fluctuations and minimize the impact of mobility. Numerical results highlight enhancements brought by the proposed framework over reference frameworks in terms of perceived quality, handover initiation time and delay constraints.

Machine Learning-Based Link Fault Identification and Localization in Complex Networks

With the proliferation of network devices and rapid development in information technology, networks such as Internet of Things are increasing in size and becoming more complex with heterogeneous wired and wireless links. In such networks, link faults may result in a link disconnection without immediate replacement or a link reconnection, e.g., a wireless node changes its access point. Identifying whether a link disconnection or a link reconnection has occurred and localizing the failed link become a challenging problem. An active probing approach requires a long time to probe the network by sending signaling messages on different paths, thus incurring significant communication delay and overhead. In this paper, we adopt a passive approach and develop a three-stage machine learning-based technique, namely ML-LFIL that identifies and localizes link faults by analyzing the measurements captured from the normal traffic flows, including aggregate flow rate, end-to-end delay and packet loss. ML-LFIL learns the traffic behavior in normal working conditions and different link fault scenarios. We train the learning model using support vector machine, multi-layer perceptron and random forest. We implement ML-LFIL and carry out extensive experiments using Mininet platform. Performance studies show that ML-LFIL achieves high accuracy while requiring much lower fault localization time compared to the active probing approach.

DEVELOPMENT OF AN OPTIMAL TECHNIQUE FOR RELIABILITY ANALYSIS OF POWER LINE COMMUNICATION SYSTEM FOR SMART GRID REALIZATION

Power Line Communication (PLC) is a communication technology that enables transmission of data on a conductor which is also used for electric power transmission. The development of a PLC system presents a significant challenge for the communication engineer due to the unusual channel characteristics that affect high-speed signal transmission since the electric power grid is designed to operate at 50/60 Hz. In addition, the topology of electric power grid network is often very irregular resulting in significant dispersion of the transmitted message signals as it is susceptible to noise and attenuation due to power lines being primarily used for transmission of electricity as a result of its viability for smart grid realization. This study therefore investigates the reliability analysis of PLC for Smart Grid (SG) realization using clipping and Turbo equalizer techniques to reduce the effects of noise and attenuation in narrowband (9-490 kHz) PLC system respectively. This optimal technique is based on the minimum Bit Error Rate (BER) search. The results show that the technique used improves the BER performance of the narrowband PLC system for smart grid realization. The result of this study provides a reliable communication and control for cost efficiency of existing power line infrastructure for Smart Grid. Keywords: PLC, Smart Grid, Attenuation, Clipping, Equalizer, Electric Power Transmission, Bit Error Rate. DOI : 10.7176/MTM/9-8-01 Publication date : August 31st 2019

Password-based Selective Linkable Convertible Ring Blind Signature

Ring signature has become an important way of privacy protection because of its anonymity and the spontaneity of ring members. It has been widely used in the field of information security. Password-based alternative linkable convertible ring blind signature scheme combines the advantages of strong anonymity of ring signature and blindness of blind signature to signature message, and adds the optional linkable and convertible characteristics, which makes it more secure than other schemes, and can also transform ring signature into ordinary signature in special occasions. At the same time, under the random oracle model, the scheme satisfies the unforgeability under the adaptive selection message attack. Performance analysis shows that the scheme has high operating efficiency.

A Robust Synchronization-Based Chaotic Secure Communication Scheme With Double-Layered and Multiple Hybrid Networks

In this paper, based on the exponential synchronization of double-layered networks composed of multiple subnets, we bring forward a chaotic secure communication scheme, which is robust to different network sizes, time-varying delays, and stochastic noise. Cluster analysis is used to process the nodes with different dynamics, such that the subnets in the transmitter and receiver are one-to-one correspondence and constitute subnet pairs, while the node size of each subnet can be inconsistent. Each subnet pair is only accountable for encrypting/decrypting a part of information. There are many encryption/decryption units and they are operating in parallel, which can not only indicate the complex characteristic of different nodes but also speed up the information encryption/decryption. The proposed scheme applies the chaotic signals yielded by many chaotic systems as key sequences, such that the key space can grow with node sizes in the transmitter. This scheme is not subject to the constraint on the amplitude of the original message and chaotic signal, the influence of time-delay and stochastic noise, and it shows that only the nodes with large degrees need to apply controllers in restoring the original information. Both theoretical analysis and numerical simulation manifest the feasibility and validity of the given scheme.

Performance of BER with Different Diversity Techniques for Millimeter-Wave Communication System

In a communications system, a diversity technique is used to enhance the reliability of a message signal by using at least two channels with different characteristics. In this paper, all four possible scenarios are considered: Single-input and singleoutput (SISO), single input and multi-output (SIMO), multipleinput and single-output (MISO), Multiple-input and multiple output (MIMO) systems. Antenna arrays will be used to reduce BER and improve the performance of the system using array gain in the line of sight channel for 60 GHz frequency in an indoor scenario. Single input and single output are investigated before analysis of multiple inputs and multiple output channel in the line of sight (LOS) and multipath propagation. MATLAB simulation has been performed using BPSK modulation. The comparative studies show that the performance of the MIMO diversity technique is more reliable in terms of BER to improve the performance and efficiency of the communication system.

Behavioral and neural aspects of the spatial processing of conspecifics signals in the electrosensory system.

Localizing the source of a signal is often as important as deciphering the signal's message. Localization mechanisms must cope with the challenges of representing the spatial information of weak, noisy signals. Comparing these strategies across modalities and model systems allows a broader understanding of the general principles shaping spatial processing. In this review we focus on the electrosensory system of knifefish and provide an overview of our current understanding of spatial processing in this system, in particular, localization of conspecific signals. We argue that many mechanisms observed in other sensory systems, such as the visual or auditory systems, have comparable implementations in the electrosensory system. Our review therefore describes a field of research with unique opportunities to provide new insights into the principles underlying spatial processing. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Pre-Grant Signaling for Energy-Efficient 5G and Beyond Mobile Devices: Method and Analysis

Due to the severely limited battery capacities, the energy efficiency of mobile devices plays an important role in their usability. In general, the cellular subsystem is one of the major contributors to the energy consumption of a mobile device, thus improving its energy efficiency is of paramount importance. In this paper, a new concept of pre-grant message together with associated control plane signaling is introduced, aiming to reduce the energy consumption of the cellular subsystem in the downlink, without notable increase in the buffering delay or latency. The proposed method is fully independent of the ordinary discontinuous reception (DRX) principle, which means that both methods can co-exist and act together to efficiently reduce the energy consumption of the user equipment. The performance of the proposed scheme in terms of the false alarm and misdetection rates are investigated and evaluated, in both additive white Gaussian noise and Rayleigh fading channels. The obtained numerical results show that the pre-grant message signaling can be decoded very reliably and can reduce the system power consumption, relative to an ordinary DRX-only reference system, by up to 70%, 68%, and 62% for FTP traffic, video streaming and VoIP, respectively, at the cost of negligible increase in the signaling overhead. The proposed method is also compared in terms of the energy consumption and energy efficiency against another state-of-the-art power-saving mechanism, namely the wake-up radio-based approach. The obtained results show that the pre-grant approach outperforms the wake-up-based system under broad range of traffic characteristics.

PUF-derived IoT identities in a zero-knowledge protocol for blockchain

As the internet of things moves into increasingly sensitive domains, connected devices need to be secured against data manipulation and counterfeiting. Where the underlying business processes involve multiple independent parties, a blockchain platform can provide a common source of truth. If changes to the common state depend on IoT devices, the authenticity and integrity of the IoT input must be ensured. Employing a blockchain platform for authenticating devices makes the process independent of the device manufacturer.This paper shows how cryptographic keys derived from a device’s physical fingerprint can be employed in a zero-knowledge protocol to authenticate a device. As the keys are regenerated at boot time rather than stored, the approach does not need an expensive secure element. An efficient implementation enables even lightweight devices to prove their identity and sign messages. Experimental results demonstrate the robustness of the approach.

Fast Verification of Signatures With Shared ECQV Implicit Certificates

In many bandwidth-critical environments, including vehicle-to-vehicle and vehicle-to-infrastructure communications, implicit certificates such as elliptic curve Qu-Vanstone (ECQV) are frequently employed as a means to reduce the bandwidth requirement of digital signatures. In these environments, however, certain recipients such as roadside units need to verify signatures for multiple messages within considerably short time periods. In this paper, we propose two efficient methods of reducing the computational costs of signature verification when multiple digital signatures are provided together with the ECQV implicit certificates. The first method achieves this by sharing the intermediate results that are computed when public keys are extracted from ECQV certificates. The second guarantees a further speed improvement by merging the public key extraction processes into a batch signature verification process. We also present an algorithm that adaptively chooses the best verification method for the given signatures in real time. Our experimental results show that the proposed methods allow for a signature verification that is five times faster than existing methods.

Performance Analysis of a Differential-Correlation Based Burst Detection Method

Burst detection is an initial step for burst-mode demodulation. The theoretical performance of a differential-correlation based burst detection (DCBD) method is analyzed. The expressions of miss detection probability and false alarm probability (FAP) of this method are derived. The FAP arisen from message signals are also considered and proved to be close to the FAP arisen from noise signals, which is not covered in other similar works. Based on the theoretical analysis, the properties of the detection method are concluded. Both the analytical analysis and the simulation results show that DCBD is robust to frequency offset and is a CFAR method. Furthermore, the detection threshold is independent of the signal amplitude. These properties indicate that DCBD is very proper and practical for burst detection. The analytical results also give references how the threshold should be set to meet the system performance requirements for various signal conditions.

Orthogonal noise-like signal symbols for broadband channel protection

The paper deals with development and analysis of particular case in a complex protection for a channel where radio messages are exchanged on the basis of mutually orthogonal signal broadband characters and alphabets based on them. The object of study is a method of secure broadband channel organization using orthogonal noise-like signal symbols. The signal broadband symbols have been synthesized in the frequency domain based on pseudo-random sequences with the subsequent orthogonalization by the Gram-Schmidt method of transformation into pre-defined spectral components of the signal symbols and subsequent transformation into the time domain with the aid of the inverse fast Fourier transform. We have proposed to deploy and explore the complex secrecy approach comprising information, structural and energy secrecies. Information secrecy is brought into action with a single use of symbols retrieved out of a certain set of alphabets. Structural secrecy is reached by deployment of signal messages filtering in the area of signal symbols merge that makes difficult to determine the duration of individual signal symbols and message separation in individual signal symbols. Therefore, the decoding of entire message becomes more difficult. Energy secrecy is ensured by hiding the radio signal in the radio noise. We have carried out modeling and analysis of information, structural and energy secrecy. Practical importance of the work lies in increasing the level of protection for broadband communication channels based of the method we proposed. The conclusions have been set up in final part of the paper.

Securing messaging services through efficient signcryption with designated equality test

To address security and privacy issues in messaging services, we present a public key signcryption scheme with designated equality test on ciphertexts (PKS-DET) in this paper. The scheme enables a sender to simultaneously encrypt and sign (signcrypt) messages, and to designate a tester to perform equality test on ciphertexts, i.e., to determine whether two ciphertexts signcrypt the same underlying plaintext message. We introduce the PKS-DET framework, present a concrete construction and formally prove its security against three types of adversaries, representing two security requirements on message confidentiality against outsiders and the designated tester, respectively, and a requirement on message unforgeability against the designated tester. We also present three extensions, analyze the efficiency of our PKS-DET construction and extensions, and compare them with related schemes in terms of ciphertext sizes and computation costs of signcryption (encryption), unsigncryption (decryption) and ciphertext equality testing. Experimental results further confirmed the practicality of our construction.

Dual-Message Amplitude Modulation (DMAM)

In this paper, a new method is proposed for AM modulation of two separate messages (dual message). The proposed method uses only one carrier and does not need any transformer or multiplexer device, while the existing methods need two carriers or a transformer or a multiplexer device for modulating a dual message. The procedure of this modulation is quite simple. First, the carrier signal is divided into positive and negative half cycles. Then, one of the message signals is inserted into positive half cycles by a simple voltage-controlled resistor (e.g., a JFET in the linear region). Another message signal is inserted into negative half cycles using the same process. Finally, the half cycles are added together and the resultant signal would have two different envelopes on negative and positive half cycles. Detection of these two messages is easy too. The demodulator consists of two simple diode detectors. One of them gets the message signal from positive half cycles, and the other gets the negative half cycles signal. Altogether, the most important advantages of this design compared to the existing methods for modulating a dual message are less power consumption and more simplicity of modulating and demodulating procedures and circuits. In addition, this method decreases the cost of the modulator system.

Quantum-Resistant Identity-Based Signature with Message Recovery and Proxy Delegation

Digital signature with proxy delegation, which is a secure ownership enforcement tool, allows an original signer to delegate signature rights to a third party called proxy, so that the proxy can sign messages on behalf of the original signer. Many real-world applications make use of this secure mechanism, e.g., digital property transfer. A traditional digital signature mechanism is required to bind a message and its signature together for verification. This may yield extra cost in bandwidth while the sizes of message and signature are relatively huge. Message recovery signature, enabling to reduce the cost of bandwidth, embeds a message into the corresponding signature; therefore, only the signature will be transmitted to the verifier and the message can further be recovered from the signature. In this paper, we, for the first time, propose a novel digital signature scheme in the identity-based context with proxy delegation and message recovery features and, more importantly, our scheme is quantum resistant, in a particular lattice-based signature. Our scheme achieves delegation information and signature existential unforgeability against adaptive chosen warrant and identity. Compared with the seminal lattice-based message recovery signature, our scheme is independent from public key infrastructure, realizes delegation transfer of signature rights, and compresses signature length ulteriorly. To the best of our knowledge, this paper is the first of its type.

Secure communication in cognitive radio networks with untrusted AF relays

SummaryIn this paper, two underlay based cognitive cooperative radio networks, each with one secondary source (SS), one secondary destination (SD), N untrusted secondary amplify and forward relays (USAFRs), one primary transmitter, and one primary receiver (PU‐RX), are considered for evaluating the secrecy performance. The SS sends the information to the SD in two time slots via multiple USAFRs in the absence of direct link between SS and SD. In the first time slot, SS and SD transmit the message and jamming signal to multiple USAFRs, respectively. In the second slot, a selected USAFR amplifies and forwards the combined received signals to the SD. The transmit powers of the secondary nodes are chosen so as to maintain the overall interference at PU‐RX below a specified limit. The transmit power of a selected USAFR is derived using the harvested energy from the RF signals of SS and SD. Two network scenarios of eavesdropping by USAFRs are studied: in one case, all USAFRs eavesdrop; while in the second case, only the selected USAFR eavesdrops the message during forwarding of the signal and power is allocated to secondary nodes on the basis of outage threshold of primary network. We investigate the secrecy outage probability (SOP) in both of the networks under several physical parameters. Analytical framework for evaluating SOP for both the cases are given while SOP in single integration form is given for the second case. MATLAB simulation results are presented for both the cases.