5 - IEEE 802.11abgn/Wi-Fi

Summary

5.1 Introduction

The 802.11 and Wi-Fi standards have become immensely successful in providing Internet connectivity for laptops. In recent years they have also started to appear in mobile phones and other portable devices to provide a moderate speed connection to Internet hotspots. They are also finding new uses that take advantage of the widely deployed infrastructure, notably in the M2M space, and in some low-power incarnations for asset tracking. The most recent release of the standard – 802.11n is beginning to garner some degree of success for audio or video streaming applications in the home. Despite these uses, almost all current deployments are targeted solely at Internet access.

802.11 is the oldest of the wireless standards covered in this book. Its genesis grew out of a proprietary wireless LAN called WaveLAN that first appeared on the market in 1988, having been started back in 1986. In its early days, it was not intended for Internet access, but as a wireless replacement for Ethernet cables, with the potential markets of factory warehousing and connection to an office network. The concept was to replace the wired physical connection of the 802.11 standard with a wireless alternative that would slot into the same 802 protocol stack. In 1991, efforts were begun to evolve it into a wireless networking standard, which led to the release of the 802.11 specification in 1997.