Appendix B

Wireless Networking Basics

This chapter provides an overview of Wireless networking.

Wireless Networking Overview

The WAG302 Access Point conforms to the Institute of Electrical and Electronics Engineers (IEEE) 802.11a, 802.11b, and 802.11g standards for wireless LANs (WLANs).

IEEE 802.11a uses Orthogonal Frequency Division Multiplexing (OFDM), a new encoding scheme that offers certain benefits over a spread spectrum in channel availability and data rate. On an 802.11a wireless link, data is transmitted in the unlicensed radio spectrum at 5GHz. The 802.11a uses OFDM to define a total of 8 non-overlapping 200 MHz channels across the 2 lower bands; each of these is divided into 52 sub carriers and each carrier is approximately 300 KHz wide. The 802.11a wireless link offers a maximum data rate of 54 Mbps, but will automatically back down to rates 48, 36, 24, 18, 12, 9, and 6 Mbps.

On an 802.11b or g wireless link, data is encoded using direct-sequence spread-spectrum (DSSS) technology and is transmitted in the unlicensed radio spectrum at 2.5GHz. The maximum data rate for the 802.11b wireless link is 11 Mbps, but it will automatically back down from 11 Mbps to 5.5, 2, and 1 Mbps when the radio signal is weak or when interference is detected. The 802.11g auto rate sensing rates are 1, 2, 5.5, 6, 9, 12, 18, 24, 36, 48, and 54 Mbps.

The 802.11 standard is also called Wireless Ethernet or Wi-Fi by the Wireless Ethernet Compatibility Alliance (WECA, see http://www.wi-fi.net), an industry standard group promoting interoperability among 802.11 devices. The 802.11 standard offers two methods for configuring a wireless network - ad hoc and infrastructure.

Infrastructure Mode

With a wireless Access Point, you can operate the wireless LAN in the infrastructure mode. This mode provides wireless connectivity to multiple wireless network devices within a fixed range or area of coverage, interacting with wireless nodes via an antenna.

Wireless Networking Basics

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NETGEAR WAG302 manual Appendix B Wireless Networking Basics, Wireless Networking Overview, Infrastructure Mode