TABLE OF CONTENTS Like any new technology, Wi-Fi can solve some problems, but create other challenges. Providing appropriate network coverage can be the most difficult issue faced when designing a wireless local area network (WLAN). This chapter, hopefully, will give the reader valuable insight and practical knowledge of different aspects of wireless networking technology, some of the general issues that each Wi-Fi flavor presents, and awareness of specific problems that may arise during implementation of the various Wi-Fi technologies. We will begin with a couple of practical deployment scenarios.
Let's explore practical deployment scenarios for both 802.1 la (current and optimized) and 802.11b, including three-cell and eight-cell configurations.
| Note | I want to thank CMP Media LLP and Jung Yee and Hossain Pezeshki-Esfahani, the authors of "Understanding Wireless LAN Performance Trade-Offs," published in the November 2002 issue of Communication Systems Design magazine, as the following text and metrics relies heavily upon that article. |
To cover areas greater than that provided by a single access point (AP), network designers may deploy multiple APs in a hexagonal cellular arrangement. Each cell has one AP at its center, so that end-users can access the WLAN from anywhere in a cell. To maintain performance levels and effective data rates, the bit error rate (BER) should not exceed 10e-5 anywhere in the network.
To make the problem tractable, assume at any given time that there is only one station, or wireless computing device, transmitting in each cell. The collision avoidance and back-off behavior of the 802.11 Media...
