Data Packet Length Research Articles

Ефективність адаптивних протоколів множинного доступу пакетних радіомереж в умовах самоподібного трафіку

Introduction. Self-similar traffic in modern telecommunication radio networks requires new methods for calculating parameters of adaptive Carrier Sense Multiple Access (CSMA) protocols, different from those adopted in classical teletraffic theory based on Poisson distribution models. Purpose. Construction of a mathematical model of the operation of adaptive synchronous CSMA protocols in conditions of self-generating traffic for three strategies for changing the length of data packets, and obtaining equations for the average transmission rate and comparing the effectiveness of adaptive control with the results of studies of the same protocols for traffic with a Poisson distribution. Methods. This goal is achieved by creating and analyzing a mathematical model of the operation of the flexible and rigid synchronous adaptive CSMA protocol for three strategies for changing the length of data packets under traffic conditions with a Pareto distribution. The model is described by the average protocol transmission rate equations, which are a function of traffic intensity, Pareto distribution parameters, and strategies for changing the length of data packets. Results. It has been proven that self-similar traffic significantly reduces the stability limit of adaptive CSMA protocols, which must be taken into account when using these protocols in radio networks with long-term dependence in traffic distribution. At the same time, the throughput of adaptive CSMA protocols remains virtually unchanged compared to the traffic model with a Poisson distribution. Conclusions. The proposed mathematical model of adaptive CSMA protocols allows to calculate the real values of the average speed, stability limit and throughput of these protocols under conditions of self-similar traffic for the proposed strategies for changing the length of data packets. The considered strategies (except for the second) are effective for adaptive control in conditions of self-generating traffic, but at a significantly lower value of traffic intensity compared to the Poisson distribution.

Intelligent Reflecting Surface-Aided Full-Duplex Covert Communications: Information Freshness Optimization

This work investigates the covert information freshness in intelligent reflecting surface (IRS)-aided communications, where a public full-duplex user (Alice) and a private full-duplex user (Bob) exchange information in the presence of a watchful warden (Willie). In particular, with the help of Alice’s undisguised signal transmission, Bob can establish covert communications such that his transmission can be shielded from Willie. Considering both the non-retransmission protocol and the automatic repeat-request (ARQ) protocol for Bob’s transmission, we study the resource allocation design. By exploiting the channel statistics, the joint design of active beamforming at Alice and Bob, the passive beamforming at the IRS, and the packet length of the confidential data packet is formulated as a nonconvex optimization problem which minimizes the age of information (AoI) at Alice for the two considered protocols taking into account the quality of service in terms of the maximum tolerable AoI at Bob and communication covertness. To circumvent the non-convexity of the design problem, we propose alternating optimization algorithms to find effective solutions. Numerical results demonstrate the superiority of our proposed optimization algorithms over various benchmarks and unveil the decrease of the optimized packet length with the improved covert channel quality.

Energy efficient machine learning based SMART-A-BLE implemented Wireless Battery Management System for both Hybrid Electric Vehicles and Battery Electric Vehicles

Electric vehicles have a larger battery pack with more than 100's cells connected in series or parallel combinations to form many battery modules. A Battery Management system (BMS) continuously monitors Current, Voltage, and Temperature data to trigger control algorithms like cell balancing and thermal management using wired communication which is then sent to the cloud for real-time analytics [1]. Wired communication restricts the flexibility in battery module assembly and makes it difficult for battery swapping. The proposed wireless communication, along with the SMART-A-BLE algorithm for BMS in the electric vehicle, uses Bluetooth Low Energy [2], [3], [4], and [5]. SMART-A-BLE algorithm predicts the best connection interval using the Decision tree model based on the link quality factor captured based on real time latency. The model uses threshold latency, expected retransmission factor, data packet length, and the number of peripherals as input features. A look-up table-based algorithm is also proposed for resource constraint devices to achieve the optimal operating point where the slaves could transmit at both low latency and low current consumption with less congestion. SMART-A-BLE control algorithm outperforms the mathematical model-based algorithm in both ideal and interference conditions within a metallic container by maintaining robust connectivity.

Energy Modeling Based on Power Profiling of Wireless Sensor Device

This article elaborates on an accurate energy model (EM) for wireless sensor devices (WSDs) based on power consumption measurement. A deep understanding of WSD’s energy cost depends on the WSD’s functional components contributing to the wireless communication process. The model includes different stages of transmission (Tx) and reception (Rx) communication modes. The practical EM is developed with data packet lengths, data rate, operation status, predesigned stages versus appropriate communication bus, and power mode, including mutual data transfers between the microcontroller and the radio module. The validity of the EM is verified through an experimental setup having a TelosB device. As expected, the modeled and measured energy consumed by the WSD operating from 1-to-4-MHz CPU frequencies and the 2-to-100-byte payload is in very good agreement. It was found that, compared to the energy consumption in processing, Tx, listening, and Rx phases, the data transfer consumes up to 40% of total WSD energy, whereas this aspect is often neglected in usual models. Overall, the proposed model provides significant accuracy and might be helpful in improving the energy efficiency of future wireless sensor networks.

Mathematical Modeling of Static Data Attribute Encryption Based on Big Data Technology

Attribute encryption is an effective one to many network communication technologies, which supports flexible access control strategies and is very suitable for fine-grained access control in large-scale information systems. In order to improve the attributes of static data, encryption technology can provide a reliable technical guarantee for network security. This paper presents a mathematical modeling method of static data attribute encryption based on big data technology. The big data redundancy elimination algorithm based on similarity calculation is analyzed. By using static data attribute encryption based on big data technology, the length of encrypted data packets will not increase, and partial redundancy of fragments can be eliminated, which can greatly improve the efficiency of the system. The attribute-based encryption mechanism uses attributes as public keys, and the decryption user is a group; so, the encryption efficiency is very high. It can realize efficient encryption and decryption, as well as flexible access control based on user attributes. This scheme can reflect the importance of attributes; so, it is more practical.

Covert Channel Construction Method Based on HTTP Composite Protocols

Aiming at the problems of low concealment of existing storage-type covert channels, high bit error rate, and low transmission rate of time-type covert channels, this paper proposes a method of constructing covert channels based on HTTP protocol combination. The method simulates browser application to send HTTP requests, dynamically distributes HTTP requests to different browsers, embeds hidden information by mathematical combination, and dynamically adjusts access objects, data packet time interval, and data packet length, thus improving the concealment of the channel. At the same time, the channel is based on the reliable transmission inside TCP protocol so that it is not affected by network jitter, thus ensuring the reliability of the channel. Experimental results show that this method can resist the detection method based on application signature, protocol fingerprint detection method, and combination model detection method, and has strong concealment. It can adjust the concealment and channel capacity according to the application scenario.

Adaptive Control at The Link Layer of the Packet Radio Networks

A mathematical model for calculating the optimal effective transmission rate at the link level of radio networks using a flexible adaptive multiple access protocol with carrier signal control and variable data frame length is proposed. This model is a tool for calculation of both the radio bandwidth network capacity and the optimal deviation of the data packet length at adaptive control of competitive access to a radio channel with a fixed strategy in conditions of significant fluctuation in traffic intensity and changes in interference intensity in the radio channel.

An Optimal Energy Utilization of Cluster Routing Protocol for Wireless Sensor Network in Restricted Area

Objectives: To efficiently monitor the highly confined area by using security measurement methods to enhance the lifetime of a large area coverage network. Methods : the modified nodes are included in the normal execution process of the network to calculate the efficiency and lifetime of the WSN. With the help of the simulation and analysis process, the proposed protocol is found to be more powerful to impact the sustainability of the network by prolonging the lifetime of the nodes. To perform this operation, the following parameters are considered: Area of the monitoring area, Number nodes, Sink portion, Energies of radio amplifier systems, Data aggregation, node electronics, and data packet length. Findings: The proposed optimal energy cluster routing protocol finds the best topological structural protocol to select the cluster head with optimal connectivity path with other nodes in a group. The data of energy utilization, data communication rate between nodes and cluster head, and analysis of the number of alive nodes concerning time are obtained. Novelty: the proposed Optimal efficient cluster routing protocol (OECRP) selects the cluster head by considering energy consumption, cluster sustainability, and its proper communication with other nodes. OECRP is used to develop the optimal topological structural protocol to connectivity path with other nodes in a group. Keywords Heterogeneous network, Low­energy adaptive clustering hierarchy (LEACH), optimal efficient cluster routing protocol (OECRP), Network lifetime, Cluster head selection

Interference Range-Reduced Cooperative Multiple Access with Optimal Relay Selection for Large Scale Wireless Networks.

Cooperative communication improves the link throughput of wireless networks through spatial diversity. However, it reduces the frequency reuse of the entire network due to the enlarged link interference range introduced by each helper. In this paper, we propose a cooperative medium access control (MAC) protocol with optimal relay selection (ORS-CMAC) for multihop, multirate large scale networks, which can reduce the interference range and improve the network throughput. Then, we investigate the performance gain achieved by these two competitive factors, i.e., the spatial frequency reuse gain and spatial diversity gain, in large scale wireless networks. The expressions of maximum network throughput for direct transmissions and cooperative transmissions in the whole network are derived as a function of the number of concurrent transmission links, data packet length, and average packet transmission time. Simulation results validate the effectiveness of the theoretical results. The theoretical and simulation results show that the helper can reduce the spatial frequency reuse slightly, and spatial diversity gain can compensate for the decrease of the spatial frequency reuse, thereby improving the network throughput from the viewpoint of the whole network.

Impact of Variable Packet Length on the Performance of Heterogeneous Multimedia Wireless Sensor Networks

Performance valuation of wireless sensor network (WSN) routing protocols calls for realistic data traffic models because of their application specific nature. Since energy limitations is a cardinal issue for WSNs, network lifetime has become a key performance metric. In the quest towards energy efficiency, data packet length is an essential factor, especially in the multimedia applications. On one hand, a modest packet length brings down the packet loss, nonetheless, it results in dissipation of more energy. Thus, there comes forth a tradeoff in resolving the data packet length, where both low and high bit rates lead to certain energy inefficiency problems. This paper analyses the effect of variable packet length, being majorly ignored by routing protocols, on the network lifetime, throughput and reliability. The presented work is validated using computer simulations.

A Study on the Impact of Packet Length on Communication in Low Power Wireless Sensor Networks Under Interference

Reliability is nowadays considered a key requirement in wireless sensor networks for their increasing diffusion in various Internet of Things applications. However, radio interference from various sources may heavily affect the performance of wirelessly connected embedded devices, resulting into increased packet collisions and congestions. There is therefore a widely recognized need of both theoretical and practical investigations capable of shedding light on the factors affecting the operativeness of sensor networks subject to interference. In this paper, we investigate the role of packet length into the reliability and energy efficiency of low-power medium access protocols. Specifically, we propose a mathematical model to explore the functional dependence of the reliability of a pair of sensor nodes under interference from packet length. We also present a wide range of experimental evaluations aimed at validating the model and at providing novel insights on dependability issues. In particular, we assess the performance of Contiki's default medium access control layer (together with that of an always listening receiver, as a baseline) in terms of packet loss rate and energy efficiency for varying payload lengths. Experimental results highlight the interplay between packet size and interference and in particular the tradeoff between the robustness against interference and the overhead imposed to communication as a function of the length of data packets. The Pareto curve describing the energy efficiency as a function of the packet loss rate, demonstrates the existence of intermediate packet size representing an optimal choice for balancing energy consumption and communication reliability, enabling adequate system dimensioning at design-level.

An Improved Channel Estimation Technique for IEEE 802.11p Standard in Vehicular Communications.

IEEE 802.11p based Dedicated Short-Range Communication (DSRC) is considered a potential wireless technology to enable transportation safety and traffic efficiency. A major challenge in the development of IEEE 802.11p technology is ensuring communication reliability in highly dynamic Vehicle-to-Vehicle (V2V) environments. The design of IEEE 802.11p does not have a sufficient number of training symbols in the time domain and pilot carriers in the frequency domain to enable accurate estimation of rapidly varying V2V channels. The channel estimation of IEEE 802.11p is preamble based, which cannot guarantee a suitable equalization in urban and highway scenarios, especially for longer length data packets. This limitation has been investigated by some research works, which suggest that one major challenge is determining an accurate means of updating channel estimate over the course of packet length while adhering to the standard. The motivation behind this article is to overcome this challenge. We have proposed an improved Constructed Data Pilot (iCDP) scheme which adheres to the standard and constructs data pilots by considering the correlation characteristics between adjacent data symbols in time domain and adjacent subcarriers in frequency domain. It is in contrast to previous schemes which considered the correlation in the time domain. The results have shown that the proposed scheme performs better than previous schemes in terms of bit error rate (BER) and root-mean-square error (RMSE).

The Optimization of the Data Packet Length in Adaptive Radio Networks

Background. Development of methods and means of the adaptive management of the radio networks bandwidth with competitive access to the radio channel. Objective. The aim of the paper is to determine the packet length effect on the effective radio networks transmission rate with taking into account the parameters, formats , and procedures of the physical and link levels at using the MAC protocol with a rigid strategy of competitive access to the radio channel. Methods. The goal is achieved by creating and analyzing the mathematical model of the effective transmission rate in radio networks. The model is described by the equation for the effective transmission rate, which is the function of both the probability of the conflict-free transmission of the MAC protocol and the coefficient of the data packet size deviation from the optimal for LLC protocol. Results. It is proved that there is the optimal deviation of the data packet length for each MAC protocol traffic intensity value, which provides the most effective transfer rate. This makes the possibility for adaptive management of the radio bandwidth by applying a pre-calculated deviation of the data packet size in dependence on the traffic intensity. Conclusions. The proposed mathematical model is the tool for calculation of both the radio bandwidth network capacity and the optimal deviation of the data packet length at adaptive management of competitive access to a radio channel with a rigid strategy at conditions of the significant fluctuation in traffic intensity.

EFFICIENT MOBILE VIDEO TRANSMISSION BASED ON A JOINT CODING SCHEME

In this paper, we propose a joint coding design which uses the Symbol Forward Error Correction (S-FEC) at the application layer. The purpose of this work is on one hand to minimize the Packet Loss Rate (PLR) and, on the other hand to maximize the visual quality of video transmitted over a wireless network (WN). The scheme proposed is founded on a FEC adaptable with the semantics of the H.264/AVC video encoding. This mechanism relies upon a rate distortion algorithm, controlling the channel code rates under the global rate constraints given by the WN. Based on a data partitioning (DP) tool, both packet type and packet length are taken into account by the proposed optimization mechanism which leads to unequal error protection (UEP). The performance of the proposed JSCC unequal error control is illustrated over wireless network by performing simulations under different channel conditions. The simulation results are then compared with an equal error protection (EEP) scheme.

Real Time FPGA-Based Ethernet Control Communication for Robotic Arm

In this paper, an approach for real time control communication using Ethernet is proposed. The strategy to support this at the network level and include Field Programmable Gate Array (FPGA) implementation on the Ethernet platform for robotic arm. An embedded Ethernet controller is designed to send data packet via Ethernet Local Area Network (LAN). The transferring data also employs Arduino Mega as the medium of communication between FPGA board and the robotic arm. It is used as the receiver to receive data packet from FPGA board with the interface of Arduino Ethernet shield. The control operation on the robotic arm is performed once the desired data packet length is reached to the Arduino Mega. SolidWorks and MATLAB software are used to design the robotic arm and simulate the robotic arm working flexibility in real world respectively. The result of the average data packet delay between FPGA boards is lower in comparison to Arduiono board. The data packet can send successfully in through the network to test the robotic arm.

Relay selection for maximizing the number of successive transmission in cooperative networks

Relay selection has an important effect on improving the performance of cooperative communication system. However, the frequent operation of relay selection can bring enormous control message overhead, and then decrease the performance of cooperative communication. To reduce the relay selection frequency, in this paper, we propose a relay selection scheme to choose the best relay considering successive packets transmission. In this scheme, through the parameters of data transmission rate, the length of data packet and the estimated channel state information, the best relay is selected to maximize the number of successive packets transmission while guaranteeing the given outage probability. It is proven by numerical results that the proposed relay selection scheme can support the successive packets transmission in cooperative wireless networks and the maximum number of successive packets transmission is affected by the different network parameters, i.e. packet length, data transmission rate, signal to noise ratio and Doppler frequency. Compared to previous relay selection schemes by simulation results, it is shown that the proposed relay selection scheme can improve the throughput performance efficiently.

Energy-Efficient and Low Signaling Overhead Cooperative Relaying With Proactive Relay Subset Selection

Energy efficient wireless communications have recently received much attention, due to the ever-increasing energy consumption of wireless communication systems. In this paper, we propose a new energy-efficient cooperative relaying scheme that selects a subset of relays before data transmission, through proactive participation of available relays using their local timers. We perform theoretical analysis of energy efficiency under maximum transmission power constraint, using practical data packet length, and taking account of the overhead for obtaining channel state information, relay selection, and cooperative beamforming. We provide the expression of average energy efficiency for the proposed scheme, and identify the optimal number and location of relays that maximize energy efficiency of the system. A closed-form approximate expression for the optimal position of relays is derived. We also perform overhead analysis for the proposed scheme and study the impact of data packet lengths on energy efficiency. The analytical and simulation results reveal that the proposed scheme exhibits significantly higher energy efficiency as compared to direct transmission, best relay selection, all relay selection, and a state-of-the-art existing cooperative relaying scheme. Moreover, the proposed scheme reduces the signaling overhead and achieves higher energy savings for larger data packets.

Packet Size Optimization for Cognitive Radio Sensor Networks Aided Internet of Things

Cognitive radio sensor networks (CRSNs) is the state-of-the-art communication paradigm for power constrained short range data communication. It is one of the potential technologies adopted for Internet of Things (IoT) and other futuristic machine-to-machine-based applications. Many of these applications are power constrained and delay sensitive. Therefore, CRSN architecture must be coupled with different adaptive and robust communication schemes to take care of the delay and energy efficiency at the same time. Considering the tradeoff that exists in terms of energy efficiency and overhead delay for a given data packet length, it is proposed to transmit the physical layer payload with an optimal packet size (OPS) depending on the network condition. Furthermore, due to the cognitive feature of CRSN architecture overhead energy consumption due to channel sensing and channel handoff plays a critical role. Based on the above premises, in this paper, we propose a heuristic exhaustive search-based Algorithm-1 and a computationally efficient suboptimal low complexity Karuh–Kuhn–Tucker (KKT) condition-based Algorithm-2 to determine the OPS in CRSN architecture using variable rate m-QAM modulation. The proposed algorithms are implemented along with two main cognitive radio assisted channel access strategies based on distributed time slotted-cognitive medium access control (DTS-CMAC) and centralized common control channel-based cognitive medium access control (CC-CMAC) and their performances are compared. The simulation results reveal that proposed Algorithm-2 outperforms Algorithm-1 by a significant margin in terms of its implementation time. For the exhaustive search-based Algorithm-1 the average time consumed to determine OPS for a given number of cognitive users is 1.2 s, while for KKT-based Algorithm-2, it is of the order of 5–10 ms. CC-CMAC with OPS is most efficient in terms of overall energy consumption but incurs more delay as compared to DTS-CMAC with OPS scheme.

English

The personal area network (PAN) coordinator can assign a guaranteed time slot (GTS) to allocate a particular duration for requested devices in IEEE 802.15.4 beacon-enabled mode. The main challenge in the GTS mechanism is how to let the PAN coordinator allocate time slot duration for the devices which request a GTS. If the allocated devices use the GTS partially or the traffic pattern is not suitable, wasted bandwidth will increase, which degrades the performance of the network. In order to overcome the abovementioned problem, this paper proposes the Partitioned GTS Allocation Scheme (PEGAS) for IEEE 802.15.4 networks. PEGAS aims to decide the precise moment for the starting time, the end, and the length of the GTS allocation for requested devices taking into account the values of the superframe order, superframe duration, data packet length, and arrival data packet rate. Our simulation results showed that the proposed mechanism outperforms the IEEE 802.15.4 standard in terms of the total number of transmitted packets, throughput, energy efficiency, latency, bandwidth utilization, and contention access period (CAP) length ratio.

Channel Efficiency with Security Enhancement for Remote Condition Monitoring of Multi Machine System Using Hybrid Huffman Coding

This paper presents a novel scheme of remote condition monitoring of multi machine system where a secured and coded data of induction machine with different parameters is communicated between a state-of-the-art dedicated hardware Units (DHU) installed at the machine terminal and a centralized PC based machine data management (MDM) software. The DHUs are built for acquisition of different parameters from the respective machines, and hence are placed at their nearby panels in order to acquire different parameters cost effectively during their running condition. The MDM software collects these data through a communication channel where all the DHUs are networked using RS485 protocol. Before transmitting, the parameter’s related data is modified with the adoption of differential pulse coded modulation (DPCM) and Huffman coding technique. It is further encrypted with a private key where different keys are used for different DHUs. In this way a data security scheme is adopted during its passage through the communication channel in order to avoid any third party attack into the channel. The hybrid mode of DPCM and Huffman coding is chosen to reduce the data packet length. A MATLAB based simulation and its practical implementation using DHUs at three machine terminals (one healthy three phase, one healthy single phase and one faulty three phase machine) proves its efficacy and usefulness for condition based maintenance of multi machine system. The data at the central control room are decrypted and decoded using MDM software. In this work it is observed that Chanel efficiency with respect to different parameter measurements has been increased very much.