Chapter 2 Introduction to WLAN Planning and Planner
Wireless Local Area Networks (WLANs) connect you instantly even while you are moving. They provide convenient and increasingly flexible productivity in today’s corporate and industrial environment. However, WLANs need to be properly planned for adequate coverage and security to get these benefits. This chapter discusses the disadvantages of poorly planned WLANs and presents Planner as the solution to such problems.
Planner plans the entire network with the help of various outdoor objects namely, buildings, trees, water bodies, indoor building objects namely, walls, windows, doors, elevator shafts, furniture, concrete columns, and metal objects; and devices such as Access Points (APs) and Sensors. The initial input to Planner is a layout image in any graphical format. As an output, it generates various RF views and then assembles these views into a comprehensive RF planning report.
2.1What is Wi‐Fi?
Wi‐Fi is another name for IEEE 802.11 based WLANs. These networks operate at and use 802.11a, 5 GHz, 802.11b/g, 2.4 GHz and the emerging 802.11n, 2.4 and 5 GHz. Wi‐Fi is promulgated by the Wi‐Fi Alliance. Products certified as Wi‐Fi compatible by Wi‐Fi Alliance are interoperable with each other even if they are from different manufacturers. You can use any brand of AP with any other brand of Client hardware that is built to the Wi‐Fi standard. Wi‐Fi has gaining acceptance in homes, offices, and public places like coffee shops, hotels, and airports.
2.2Disadvantages of Poorly Planned WLANs
Poorly planned WLANs have the following risks:
•Low Performance: Lack of coverage, capacity, and throughput planning results in poor connectivity speeds in certain areas. This could result in low performance of the network.
•High Security Risk: RF signals spill due to the very nature of the wireless network environment. For example, hackers could tap into the WLAN from the parking lot or the street. This can lead to serious security breaches.
•Bad User Experience: Low performance, throughput, or coverage lead to bad user experience.
•High Operational Expenses (OPEX): Network administrators have to spend a lot of time and effort in troubleshooting issues, quality of service, and security exposure after the deployment of networks. This leads to higher operational expenses.
•Lower Return on Investment (RoI): A poorly planned network results in a lower RoI as the productivity gains are not as high as predicted.
The current state‐of‐the‐art is to carry out a site survey (also called radio survey), use best practices for AP placement, or even perform deployment on ad hoc basis. These methods have the following limitations:
•Site surveys are time consuming, expensive, and prone to errors.
•Ad hoc deployments pose difficulty in visualizing network coverage, lead to security exposure, and cause channel interference.
•‘What‐If’ scenarios are not possible in site survey or ad hoc deployment methods.
There is no established practice for planning WLAN security networks, an essential part of IT security in today’s network environment.
Pre‐deployment enables successful WLAN deployments by:•Maximizing network coverage and throughput
•Minimizing channel interference
•Minimizing security exposure by ensuring minimum signal spillage outside the designated area of WLAN operation
•Providing ‘What‐If’ scenarios for trade‐off between security exposure due to signal spillage and network coverage
•Maximizing the detection and prevention range of WLAN security Sensors
•Planning Sensors to ensure reliable location tracking of unauthorized devices
•Ensuring that even the weakest transmitter is detected and prevented by the Sensors
•Planning to enable live 24x7 RF monitoring
•Troubleshooting remotely
•Restructuring the whole plan especially while extending the existing office space or deploying new equipments
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