Статьи журнала - International Journal of Computer Network and Information Security
Все статьи: 1066
Wavelength switching delay and distribution in optical fiber networks
Статья научная
Advanced network engineering is rapidly evolving and providing ever larger levels of communications capacity. This work explores deployed wavelength division modulation (WDM) optical networks and the flexible light path scheduling problems. Light path switching can improve the performance of routing and wavelength allocation (RWA) in WDM by relaxing the continuity constraint and consequently reducing connection request blocking probability during RWA process. Through extensive simulations, we are able to conclude that our proposed delayed allocation (DA) algorithm with wavelength switching improves resource consumption efficiency and lowers call blocking. We also evaluate demands with limited wavelength switching such that a reason- able result can be specified. This wavelength switching is found to significantly increase the performance improvement of DA.
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Weighted Round Robin and Rate Limiter based Fair Queuing for WRR
Статья научная
In this paper we present a new packet scheduling method based on parallel usage of multiple WRR schedulers, rate limiters and output bandwidth calculation for modern NGN networks. The main idea of the presented method is to provide queueing fairness within queues. The method provides the same results in output bandwidth allocation as the compared algorithm, while within one queue flows with different packet size and arrival rates gets the same output bandwidth. With this method we are able to achieve the overall result of bandwidth assignment as algorithms like WRR, WFQ, WRRPQ and LLQ by only changing the mathematical model used to calculate the bandwidth assignment. We call this method Weighted Round Robin and Rate Limiter based Fair Queuing (WRRRLbFQ). We prove the model outcome with simulation results using NS2 simulator and compare the behavior with the WRR scheduler.
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Wi-Fi Networks Security and Accessing Control
Статья научная
As wireless networks access gains popularity in corporate, private and personal networks, the nature of wireless networks opens up new possibilities for network attacks. This paper negotiating Wi-Fi security against scanning of rogue Wi-Fi networks and other related activities and considers the monitoring of Wi-Fi traffic effects. The unauthorized access point (AP) problem has raised more attention and resulted in obtaining wireless access without subscriber permission. This work assumes Wi-Fi AP under attack specially rogue AP and/or ad-hoc client. It provides a solution for detecting and preventing this attack. In addition, it provides the required user permissions to allow/block access of the files on the user of ad-hoc client. The experiments include the rogue AP attack are maintained and the effectiveness of the proposed solution are tested.
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Wireless wearable smart healthcare monitoring using android
Статья научная
The healthcare monitoring system is very useful for the old age people, cardiac vascular endues and many others for observing vital parameters like blood pressure, heart rate, pulse rate, body temperature etc. The proposed work utilizes 8bit X-Mega2560 microcontroller with an application created for overseers and hospital to constantly watch the patient’s parameters from their home, hospitals etc. The proposed system senses the vital parameters of the patients and sends an alert message to respective caretakers, through Wi-Fi which utilizes COAP conventions. These models are integrated to a simple arduino uno microcontroller to exhibit different functionalities. The system will reduce the cost, empowering the patients who are not able to consult the doctors for diagnosis and also minimize the patient’s transportations. This system will bridge the gap between patient and doctor in real time.
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a novel energy efficient routing protocol EACBM for scalable wireless sensor networks
Статья научная
Recent advancements in the field of wireless communication results in the improvement of Wireless Sensor Networks (WSNs) having low powered, low cost and smallest multi-operational sensing units called Sensor Nodes (SNs). The limited battery life of these SNs is the major issue of WSNs. The dissipation of SN energy for transmitting information of one SN to Base Station (BS) is the major cause of depletion of SN energy. Also, SNs energy is in direct relation with battery lifetime of WSNs. Due to which WSN is affected in terms of scalability, a lifetime of network and energy efficiency. Many routing protocols have been proposed to overcome this issue and clustering is the most dominant scheme in which the whole network is divided into small clusters. This clustering scheme is based on the principle of divide and conquers along with data aggregation. In this paper, authors propose a new routing protocol i.e. Energy Aware Cluster Based Multi-hop (EACBM) which uses the principle of clustering and multi-hop communication pattern for transferring information to BS. So that minimum SNs energy is consumed and hence increases the lifetime of WSN. It also uses the concept of sub-clustering to cover those areas of SNs where CH cannot reach to gather information or which cannot take part in any clustering process due to its far away position. Simulation results show that energy efficiency is greatly optimized by reducing the number of transmission distance between CH and BS via multi-hopping. It also shows how network lifetime, packets transmitted to BS and CH and number of dead SNs is affected by scaling i.e. by different network sizes (100*100m2; 500*500m2 and 1000*1000m2) in EACBM by comparing it with SEP, LEACH, CEEC and LEFCA routing protocols.
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Статья научная
The underwater acoustic environment is a promising technology which explores the real-time data collection for various applications. However, these channels are prone to errors, and characterized by propagation delay, half duplex communication. At low frequencies, the fading phenomenon extensively affect the behavior of the channel and hence the effect the design of reliable communication system. The underwater acoustic channels to perform appreciably reliable communication, an attempt are made by various modulation and coding techniques. Simulation esults for the combination of BPSK modulation with Reed Solomon code (BPSK-RS) having various interleavers Random Interleaver, Matrix Interleaver, have been investigated. To improve the Bit Error Rate performance various modulation techniques such as BPSK, QPSK, and QAM were combined with coding algorithms like RS code, Turbo code and different Interleavers. The investigation of the above combination reveals that IDMA-OFDM-MIMO with BPSK modulation, Turbo code with Random Interleaver technique improves significantly Bit Error Rate performance.
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