38 research outputs found
A cross-layer adaptive mechanism for low-power wireless personal area networks
This article presents a novel method providing reliable data links for low-power wireless personal area networks. The method implements a dynamic frame formation using hamming-codes. The formation process is made in an optimum way to obtain high throughput while questioning channel condition in the network. A cross-layer interaction is utilized to get noise resilient link layer operations. This interaction is achieved by querying the value of bit error rate from the physical layer. The method is adapted to be used in low power and low-rate wireless networks based on IEEE 802.15.4 protocol. Performance metrics are evaluated through extensive Monte Carlo simulations and its success is compared to IEEE 802.15.4 and IEEE 802.15.4g protocol outputs. The simulations are made over various communication types using high traffic loads. In all our experiments, the proposed method substantially increases communication throughput, reduces energy consumption, and increases network life-time. (C) 2015 Elsevier B.V. All rights reserved
A real-time noise resilient data link layer mechanism for unslotted IEEE 802.15.4 networks
Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 is a protocol operating in media access control and physical layer, and it is commonly used in low-power and low data-rate wireless communications. In this paper, we develop a stochastic model for unslotted operations of IEEE 802.15.4 networks. Signal fading is an important factor in mobile communications. According to the level of fading, signal-to-noise ratio gets dynamically changing values. Given a pair of nodes communicating to each-other in a mobile channel, the model calculates frame sizes providing maximum data-rate of successful IEEE 802.15.4 transmissions. The experimental results in various environments are given in the paper to discuss the success of the model. In the consideration of real-time operations, the model is improved to be operated in a low-complexity hardware/software unit. According to experimental results presented in the paper, the proposed model seems to be suitable in mobile environments by achieving high data-transfer rate for unslotted IEEE 802.15.4 protocol. Copyright (c) 2015 John Wiley & Sons, Ltd
Slotsuz IEEE 802.15.4 Ağlarda CSMA/CA Parametre Değerlerinin Hesabına Yönelik Monte Carlo Makinesinin Tasarımı
A Monte Carlo Machine Design to Obtain CSMA/CA Parameter Values for Unslotted IEEE 802.15.4 Based Networks
IEEE 802.15.4 protocol is often used in wireless personal area networks. The protocol, which consumes low energy and has low computational complexity, is preferred in many applications.
Assigning the best suitable values to CSMA/CA parameters, which are used for accessing the channel, is an important task that affects the communication performance. These values are variables depending on network type and network traffic. In this paper, tests were made according to network types using Monte Carlo simulations and the best values were found. The impact of
parameters is observed while obtaining these values for the corresponding network type under various data traffic. The impact of calculated values using Monte Carlo machine, which is designed for this process, is analyzed. The best parameter values for various network types and network traffics are proposed to network designers
Kablosuz ağlarda şifreleme algoritmalarının performans analizi
İnternette yaygın veri kullanımı ve kapsitesi her geçen gün hızla artmaktadır. Bu nedenle bu verilerin aktarımı veya iletimi sırasında veri güvenliği önem arz etmekle birlikte bir çok veri şifreleme algoritmaları kullanılmaktadır. Literatürde en yaygın kullanılan algoritma çeşitleri TEA, XTEA, AES, DES, RSA, RC5 algoritmalarıdır. Literatürde bu şifreleme algoritmalarının performans analizi ile ilgili bir çok çalışma bulunmasına rağmen bunların altısının birbiri ile kıyaslanması hakkında çalışma bulunmamaktadır. Bu çalışmada literatürden farklı olarak bu altı algoritma gerçekleşme süresi ve dosya boyutu bakımından karşılaştırılarak birbirlerine göre üstünlükleri veya dezavantajları incelenmiştir.The widespread usage and capacity of the internet is rapidly increasing day by day. For this reason, data security is
important during transmission or transmission of these data. To provide this security, many data encryption
algorithms are used. The most widely used algorithm types in the literature are TEA, XTEA, AES, DES, RSA, Rc5
algorithms. Although there are many studies about the performance analysis of these encryption algorithms in the
literature, there is no study about the comparison of the six of them. In this study, the six algorithms were compared
in terms of actualization time and file size, and their advantages or disadvantages were examined
MAC PERFORMANCE ANALYSIS OF IEEE 802.15.4 PROTOCOL WITH BCH CODING
The subject of this paper includes the effect of MAC performance analysis for IEEE 802.15.4 protocol with BCH coding. To analyse the performance, data transmissions are made for different communication environments with different scenarious using BCH coding. Performance results are observed as changing values on MAC parameters. These parameters are composed of average transmission time, transmitted data amount and packet loss