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A distributed system is presented for the monitoring and control of the primary variables: pressure, level and flow; for this, a wireless system is implemented at the level of sensor-actuators and at the level of controllers an Ethernet / IP network, the mentioned industrial networks are implemented based on the OSI model and TCP / IP respectively, for the visualization an HMI is realized in the software...
The rapid growth of WLAN over past few years has increased immensely in academia as well as in every industry, but many weaknesses are there in ad hoc network, due to this many attackers are really passionate towards authorization. For the authentication defense mechanism and wireless monitoring has become a vital component of computer security to predict and prevent attacks. In this paper, we explain...
IEEE 802.11 WLANs use carrier sense multiple access with collision avoidance (CSMA/CA) to initiate the Request to Send / Clear to Send (RTS/CTS) handshaking mechanism that solves the hidden node problem. However RTS/CTS also causes the exposed node problem where a node is unnecessarily prevented from accessing the wireless channel even when such access will not disrupt another nodes ongoing transmission...
As the widespread deployment and usage of 802.11-based wireless local area networks (WLANs), Wi-Fi users are vulnerable to be attacked by a security threat called evil twins. The evil twin, a kind of rogue access points (RAPs), masquerades as a legitimate access point (AP) to lure users to connect it. Malicious adversaries can easily configure evil twins on a laptop to induce victim wireless users...
Wireless local area network (WLAN) uses carrier sens multiple access with collision avoidance (CSMA/CA) to share wireless medium. However, in dense WLAN environment, it occurs interference between WLAN nodes such as access points (APs) and stations (STAs). For resolving this problem, we propose management of WLAN APs by using open network operating system (ONOS) controller which is one of software...
within this paper the use of Wi-Fi in air and underwater environment using the channels around the 2.4 GHz frequency range that have been standardized worldwide, is presented through simulation and experimental work. Using a bow-tie shaped antenna we study the actual signal strength between underwater and air conditions, while changing the distance between two devices, wirelessly connected with each...
The most severe challenge faced by the wireless networks in supporting real time communications is sharing of wireless channel. A Wireless Token Passing Network (WTPN) is the one that utilizes token passing approaches for sharing the wireless medium. The token passing approaches are characterised by passing the tokens in the wireless local area network and the station that holds the token gets the...
Fingerprint positioning is considered to be one of the most promising indoor positioning technique. The most significant technological bottleneck of fingerprint positioning technology is the high labor cost of the radio map establishing process. Many radio map fast establishing algorithms were proposed to solve this problem. There is no evaluation norm for these algorithms but positioning accuracy,...
The increase of wireless devices due to the implementation of wireless sensor networks, cyber-physical systems with wireless communication interfaces and mobile monitoring as well as the installation of diagnosis applications into the shop floor improves real-time transparency of machine conditions and production processes. For a minimal invasive integration of such technologies into the brownfield...
Wireless control systems for factory automation (FA) applications are subject to coexistence impairments, especially in license-free spectrum bands. Evaluating the coexistence impact requires the knowledge of appropriate characteristic parameters and the usage of a suitable simulation method. In this paper we propose an integral approach for the event-based simulation of wireless coexisting close-loop...
The smart grid a new generation of standard power distribution grid. The communication infrastructure is critical for the successful operation of the modern smart grids. The use of communication technologies ensures the reduction of energy consumption, optimal operation of the smart grid and coordination between all smart grids' components from generation to the end users. This paper presents an overview...
Indoor positioning has gained more importance with the recent emerging technologies including Internet of things or mobile applications using the location information of the client. The main of this work is an indoor positioning method to be used in swarm robotic applications using Bluetooth or Wi-Fi standart metrics. While the main work includes fusion of several location estimation methods by setting...
IEEE 802.11 Wireless Local Area Networks are an appealing complement, if not an alternative, to Ethernet-based industrial solutions because it not only can match Ethernet's high throughput but also leads to reduced costs and more system-design flexibility. However, like in Ethernet, clock synchronization service for applications has not been inherently present in IEEE 802.11. This paper analyzes the...
The proliferation of RF networks coupled with the diverse and growing set of mobile devices, opened the doors for a new class of context awareness through contact-free ambient sensing. Since our initial challenges paper in 2007, the field of device-free passive sensing has witnessed an exponential growth; covering areas such as intrusion detection, mobile healthcare, whole-home gesture recognition,...
Wireless body area networks have recently gained attention, mainly after the IEEE 802.15.6 standard had been proposed. Reviewing the literature, we easily recognize that several authors use different terminologies for a single concept or a single terminology for different concepts. This generates confusion and blocks fair comparisons between systems. In this paper, we present an overview of Wireless...
Radio frequency interference in wireless networks affects data packets which are transmitted over WiFi networks and the data packets are lost due to poor signal strength during transmission. This study presents Access Point s' (APs') performance and analyse co-channel, adjacent channel interference of IEEE 802.11 operating at 2.4 Ghz and 5 Ghz frequency bands at the Namibia University of Science and...
A dense multi-hop wireless sensor network usually faces a scalability problem since the distance between cluster heads could be high, which causes relatively low throughput and high latency between the sink node and cluster heads. In this paper, we propose a heterogeneous structure for a dense WSN using IEEE 802.15.4 and IEEE 802.11 networks to increase throughput and reduce latency. However, since...
This paper describes a design of network structure which combines Wireless Local Area Network (LAN) and Wireless Sensor Network (WSN). The network topology is employed in an enterprise scenario. At hardware side, we have designed a slim Access Point (AP) with embedded OpenWRT Linux System and a ZigBee Dongle and integrated them in a Plug and Play (PnP) manner. The ZigBee dongle has a programmer-friendly...
In this paper, we investigate issues of fairness and spatial reuse in heterogeneous wireless local area networks (WLANs) based on IEEE 802.11ax. According to discussions in the evolving IEEE 802.11ax standardization, the value of carrier sensing threshold (CSTH) needs to be increased, in order to improve spectral efficiency of WLANs by means of spatial reuse. We reveal a serious problem of unfairness,...
MAC interference in IEEE 802.11 network is caused by overlapped signal ranges and complex carrier sensing topology. Data throughput and wireless coverage increases by sender's transmission power in free space and this property identified the transmission power as a standard indication for wireless efficiency; however, increased transmission power also implies longer reachable signal range and higher...
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