Wireless local area network

Any location that has a connection to the SCADA network is a target, especially unmanned or unguarded remote sites. Conduct a physical security survey and inventory access points at each facility that has a connection to the SCADA system. Identify and assess any source of information including remote telephone/ computer network/fiber optic cables that could be tapped radio and microwave links that are exploitable computer terminals that could be accessed and wireless local area network access points. Identify and eliminate single points of failure. The security of the site must be adequate to detect or prevent unauthorized access. Do not allow live network access points at remote, unguarded sites simply for convenience. 

Chan, T. M., Man, K. F., Tang, K. S. and Kwong, S. (2005b). Optimization of wireless local area network in IC factory using a jumping-gene paradigm, 5 IEEE International Conference on Industrial Informatics (INDIN), pp. 773-778. 

Wireless networks will enable people on the move to communicate with anyone, anywhere, at any time, via a range of multimedia services. Wireless networks will form virtual offices anywhere in the world from small hand-held devices that provide seamless telephone, modem, fax, and computer communications. Wireless local area networks (LANs) will connect palmtop, laptop, and desktop computers anywhere in an office building or on a campus, as well as in the corner cafe. In the home, LANs will enable a new class of intelligent home electronics that can interact with each other and with the Internet. Video teleconferencing will be possible between buildings that are blocks or continents... 

Taheri A, Singh A, Agu E (2004) Location fingerprinting on infrastructure 802.11 wireless local area networks. In LCN 04 Proceedings of the 29th annual IEEE international conference on Local Computer Networks, IEEE Computer Society, pp 676-683. Washington, DC, USA... 

The communication infrastructure in a WSN consists of two layers the first layer between the sensors and the gateways and the second between the gateways and the outside world [10]. While for the backbone network, ie, the second layer, fast and secure lines, eg, optical hbers, are preferred, for the hrst layer the choices vary. According to the distance and the demanded speed, two different transmission categories can be found (1) wireless local area network (WLAN) and (2) wireless personal area network (WPAN), [20]. These transmission categories are briefly described in the next sections. 

Wi-Fi Trademark of the Wi-Fi Alliance used to describe a group of wireless local area network devices based on the IEEE 802.11 standard. 

Wireless Local Area Networks. Wireless networks go back to the Aloha data network and microwave connectivity of data centers in the 1970 s. By 1980, a number of scientists were investigating how wireless... 

One important application of spread spectrum communication systems is in the implementation of wireless local area networks (LANs). The attraction of such networks is obvious. A computer with access to a wireless LAN is completely untethered and a hard (wired) connection to a network is unnecessary. Wireless LANs are clearly advantageous in a situation in which computers are highly mobile (roaming), such as with laptop computers being moved from office to office or from an office to a conference room. Each computer carries its own RF transmitter and receiver, and such a system becomes very practical if licensing requirements can be avoided. 

In this section, we designed a flexible multiband antenna based on the aforementioned embroidered textiles. The proposed antenna operates at Global System for Mobile Communications (GSM 850/900 MHz), Personal Communications Service (PCS 1800/ 1900 MHz), and Wireless Local Area Network (WLAN 2450 MHz) bands. As demonstrated in Wang et al. (2014), an important aspect of this antenna is the loaded loop. 

Another main strand in access provision concerns Wireless Local Area Networks (WLAN) and mobile networks. In terms of hardware and signal processing WLANs are based on standardized industry technologies. The three main solutions are variants of the IEEE 802.11 standard (802.11a, 802.11b and 802.11 g). Subsets (a) and (g) provide theoretical speed of 54 Mbps and the (b) standard 11 Mbps. These are also used in studied case networks. Questions of standardization and interoperability between the different technology domains remain one of the main challenges. 

The principle of a factory-wide network of production machines, however, allows a number of other applications. It is, for example, possible to access the status of a production plant anywhere in the world via the Internet - an aspect that should not be underestimated in the course of globalization. In addition, information about each production order, such as the causes of machine standstill, can be entered and recorded by the employees in production using so-called handheld personal digital assistants (PDA) via wireless local area networks (LAN). This information is finally collected and documented on the central server through the network. 

A Virtual Automation Network (VAN) [12] [13] [14] is a heterogeneous network consisting of wired and wireless Local Area Networks, the Internet and wired and/or wireless communication systems. VAN is not a new set of protocols it aims at reusing as much as possible from the LAN, WAN and industrial communication. The aim of VAN is to transfer data through a heterogeneous network, through an end-to-end communication path, in the context of an automation application. 

IEEE 802.11 Set of standards for implementing Wireless Local Area Network (WLAN) computer communication in the 2.4, 3.6,and 5 GHz frequency bands. 

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